UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, DC 20549
FORM 6-K
REPORT OF FOREIGN PRIVATE ISSUER
PURSUANT TO RULE 13a-16 OR 15d-16 OF
THE SECURITIES EXCHANGE ACT OF 1934
Report on Form 6-K dated March 29, 2019
Commission File Number 1-14846
AngloGold Ashanti Limited
(Name of registrant)
76 Rahima Moosa Street
Newtown, 2001
(P.O. Box 62117, Marshalltown, 2107)
South Africa
(Address of principal executive offices)
Indicate by check mark whether the registrant files or will file annual reports under cover of Form
20-F or Form 40-F.
Form 20-F X
Form 40-F
Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by
Regulation S-T Rule 101(b)(1):
Yes
No X
Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by
Regulation S-T Rule 101(b)(7):
Yes
No X
Indicate by check mark whether the registrant by furnishing the information contained in this Form
is also thereby furnishing the information to the Commission pursuant to Rule 12g3-2(b) under the
Securities Exchange Act of 1934.
Yes
No X
Enclosure: Press release ANGLOGOLD ASHANTI LIMITED – MINERAL RESOURCE AND ORE
RESERVE REPORT FOR THE YEAR ENDED DECEMBER 31, 2018
SUITE OF REPORTS
<IR>
<SDR>
<NOM>
<R&R>
<AFS>
MINERAL RESOURCE
AND ORE RESERVE
REPORT
2018
CONTENTS
OUR 2018 SUITE OF REPORTS
SECTION 1
INTRODUCTION
1
2
SECTION 2
SOUTH AFRICA
1
20
SECTION 3
CONTINENTAL AFRICA
1
46
SECTION 4
AUSTRALASIA
1
136
SECTION 5
AMERICAS
1
160
SECTION 6
ADMINISTRATIVE INFORMATION
1
252
AngloGold Ashanti publishes a suite of reports annually to record our overall performance. While the
Integrated Report 2018 is our primary report, it should be read in conjunction with this report, the
Mineral Resource and Ore Reserve Report 2018, as well as the other reports making up our full suite of
reports for the year.
Integrated Report 2018 is our primary report, it should be read in conjunction with this report, the
Mineral Resource and Ore Reserve Report 2018, as well as the other reports making up our full suite of
reports for the year.
This document provides shareholders with the information required to enable them to make informed decisions regarding the
resolutions to be voted on at the company’s annual general meeting for shareholders. Details on these resolutions are also provided.
This document is distributed to all AngloGold Ashanti shareholders.
resolutions to be voted on at the company’s annual general meeting for shareholders. Details on these resolutions are also provided.
This document is distributed to all AngloGold Ashanti shareholders.
In compliance with the rules governing its listing on the New York Stock Exchange (NYSE), AngloGold Ashanti prepares a report on
Form 20-F which is led annually with the United States Securities and Exchange Commission (SEC).
Form 20-F which is led annually with the United States Securities and Exchange Commission (SEC).
As this Notice of Annual General Meeting does not provide a holistic assessment of the group’s business, performance, risks or
prospects, it should be read in conjunction with other reports making up AngloGold Ashanti’s 2018 annual reports. These are:
prospects, it should be read in conjunction with other reports making up AngloGold Ashanti’s 2018 annual reports. These are:
<IR>
Integrated Report
•
The primary
document in our
suite of reports
document in our
suite of reports
•
Provides a
comprehensive
overview of our
performance
in relation to
our strategic
objectives and the
outlook for the
company
comprehensive
overview of our
performance
in relation to
our strategic
objectives and the
outlook for the
company
•
Both financial
and non-financial
performance are
reviewed
and non-financial
performance are
reviewed
•
Complies with the
IIRC framework,
King IV and
the JSE and
NYSE listings
requirements
IIRC framework,
King IV and
the JSE and
NYSE listings
requirements
<NOM>
Notice of Annual
General Meeting
and Summarised
Financial
Information (Notice
of Meeting)
General Meeting
and Summarised
Financial
Information (Notice
of Meeting)
•
Notice of
forthcoming
annual general
meeting
forthcoming
annual general
meeting
•
Description of
resolutions to be
voted on
resolutions to be
voted on
•
Remuneration
policy and
implementation
report
policy and
implementation
report
•
Summarised
financial
information
<SDR>
Sustainable
Development
Report
Development
Report
•
Describes
commitment
to sustainable
development
commitment
to sustainable
development
•
Provides detail on
socio-economic
and environmental
performance in
relation to material
issues
socio-economic
and environmental
performance in
relation to material
issues
•
Complies with
GRI Standards
and is aligned with
the UN Global
Compact and
UN Sustainable
Development
Goals (SDGs)
GRI Standards
and is aligned with
the UN Global
Compact and
UN Sustainable
Development
Goals (SDGs)
•
Independently
assured
assured
<R&R>
Mineral Resource
and Ore Reserve
Report
and Ore Reserve
Report
•
Detailed
breakdown of our
Mineral Resource
and Ore Reserve
– at group and
operational level
breakdown of our
Mineral Resource
and Ore Reserve
– at group and
operational level
•
Complies with
SAMREC and
JORC, as well as
Section 12.11 of
the JSE Listings
Requirements
SAMREC and
JORC, as well as
Section 12.11 of
the JSE Listings
Requirements
•
Signed off by
Competent
Person
Competent
Person
<AFS>
Annual Financial
Statements
Statements
•
Prepared in
accordance with
the International
Financial
Reporting
Standards
(IFRS); the
requirements of
the South African
Companies Act,
no 71 of 2008,
as amended;
the JSE Listings
Requirements and
King IV
accordance with
the International
Financial
Reporting
Standards
(IFRS); the
requirements of
the South African
Companies Act,
no 71 of 2008,
as amended;
the JSE Listings
Requirements and
King IV
•
Audited in
accordance with
International
Standards on
Auditing
accordance with
International
Standards on
Auditing
•
Includes the
Directors’ report
Directors’ report
<WWW>
Our dedicated annual
reporting website,
hosts PDFs of the
full suite of reports
to facilitate ease
of access by and
communication with
stakeholders.
reporting website,
hosts PDFs of the
full suite of reports
to facilitate ease
of access by and
communication with
stakeholders.
Scan to visit the
mobile website
mobile website
www.aga-reports.com
Houses the full suite
of 2018 reports
together with
supplementary
information
All these reports are available online at www.aga-reports.com
Printed copies of these reports are available on request from the company
SECTION 1 / INTRODUCTION
ABOUT THIS REPORT
The Mineral Resource and Ore Reserve for AngloGold Ashanti Limited (AngloGold Ashanti) are
reported in accordance with the minimum standards prescribed by the South African Code for the
Reporting of Exploration Results, Mineral Resources and Mineral Reserves (the SAMREC Code,
2016 edition), and also conform to the standards set out in the Australasian Code for Reporting
of Exploration Results, Mineral Resources and Ore Reserves (JORC Code, 2012 edition).
reported in accordance with the minimum standards prescribed by the South African Code for the
Reporting of Exploration Results, Mineral Resources and Mineral Reserves (the SAMREC Code,
2016 edition), and also conform to the standards set out in the Australasian Code for Reporting
of Exploration Results, Mineral Resources and Ore Reserves (JORC Code, 2012 edition).
The reporting criteria, as outlined in the reporting codes, have been used in the preparation of internal Competent Person reports
(CPR) for each operation, from which the numbers stated in this report have been drawn. Reporting is also in accordance with
Section 12 of the Johannesburg Stock Exchange (JSE) Listings Requirements.
The Mineral Resource, as reported, is inclusive of the Ore Reserve component unless otherwise stated. Mineral Resource and
Ore Reserve are reported as at 31 December 2018, net of 2018 production depletion.
Information is presented by operating region, country, mine and project. The following tables and graphs are used to illustrate details
across AngloGold Ashanti’s operations during 2018: infrastructure maps; legal aspects and tenure, inclusive Mineral Resource and
Ore Reserve comparison by region, country, mine and project, details of average drill hole/sampling spacing and type, geological
cross sections and Mineral Resource sensitivities, exclusive Mineral Resource, Mineral Resource below infrastructure, inclusive
Mineral Resource and Ore Reserve by-products, year-on-year reconciliation of the Mineral Resource and Ore Reserve, Inferred
Mineral Resource in business plan, Ore Reserve modifying factors, grade tonnage information on the Mineral Resource and details
of appointed Competent Persons. Topics for brief discussion include regional overview, country overview, introduction, geology,
exploration, projects and estimation.
PLEASE NOTE:
The following should be noted in respect of our report:
•
All figures are expressed on an attributable basis unless otherwise indicated
•
Unless otherwise stated, $ or dollar refers to US dollars throughout
•
Locations on maps are indicative
•
Group and company are used interchangeably
•
Mine, operation and business unit are used interchangeably
•
Rounding off of numbers may result in computational discrepancies
•
To reflect that figures are not precise calculations and that there is uncertainty in their estimation, AngloGold Ashanti reports
tonnage, content for gold, silver and uranium to two decimals and copper, sulphur and molydenum content with no decimals
•
Metric tonnes are used throughout this report
•
For terminology used in this report, please refer to the glossary of terms on page 257
•
All grade tonnage curves reflect the Mineral Resource and exclude stockpiles unless otherwise stated
1
SECTION 1 / INTRODUCTION
CONTENTS
Group profile
3
Corporate governance
4
The year in review
6
Group overview
11
INTRODUCTION
Ghana – Obuasi
2
SECTION 1 / INTRODUCTION
GROUP PROFILE
LOCATION OF ANGLOGOLD ASHANTI’S
OPERATIONS AND PROJECTS
Our operations and projects are grouped regionally as follows:
SOUTH AFRICA
CONTINENTAL AFRICA
Democratic Republic of the Congo, Ghana, Guinea, Mali and Tanzania
AUSTRALASIA
Australia
AMERICAS
Argentina, Brazil, Colombia
Percentages indicate the ownership interest held by AngloGold Ashanti.
All operations are 100%-owned unless otherwise indicated.
Project
Operation
3
SECTION 1 / INTRODUCTION
CORPORATE GOVERNANCE
AngloGold Ashanti reports its Mineral Resource and Ore Reserve in accordance with the minimum
standards prescribed by the South African Code for the Reporting of Exploration Results, Mineral
Resources and Mineral Reserves (the SAMREC Code, 2016 edition), and also conform to the standards
set out in the Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore
Reserves (JORC Code, 2012 edition).
standards prescribed by the South African Code for the Reporting of Exploration Results, Mineral
Resources and Mineral Reserves (the SAMREC Code, 2016 edition), and also conform to the standards
set out in the Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore
Reserves (JORC Code, 2012 edition).
AngloGold Ashanti achieves this through ensuring the principles of integrity, transparency and materiality are central to the
compilation of this report and through using the reporting criteria and definitions as detailed in the SAMREC code. In complying with
revisions to the SAMREC Code, the changes to AngloGold Ashanti’s Mineral Resource and Ore Reserve have been reviewed and
it was concluded that none of the changes are material to the overall valuation of the company. AngloGold Ashanti has therefore
once again resolved not to provide the detailed reporting as defined in Table 1 of the code, apart from the maiden Ore Reserve
declaration for Quebradona. The company will however continue to provide the high level of detail it has in previous years in order to
comply with the transparency requirements of the code.
AngloGold Ashanti established a Mineral Resource and Ore Reserve Steering Committee (RRSC), which is responsible for setting
and overseeing the company’s Mineral Resource and Ore Reserve governance framework and for ensuring that it meets the
company’s goals and objectives while complying with all relevant regulatory codes. Its membership and terms of references are
mandated under a policy document signed by the Chief Executive Officer.
For more than a decade, the company has developed and implemented a rigorous system of internal and external reviews aimed
at providing assurance in respect of Ore Reserve and Mineral Resource estimates. The following operations were subject to an
external review in line with the policy that each operation/project will be reviewed by an independent third party on average once
every three years:
•
Mineral Resource and Ore Reserve at Iduapriem
•
Mineral Resource and Ore Reserve at Sunrise Dam
•
Mineral Resource and Ore Reserve at Cerro Vanguardia
•
Mineral Resource and Ore Reserve at Serra Grande
•
Mineral Resource and Ore Reserve at Quebradona
The external reviews were conducted by Pivot Mining Consultants Pty (Limited), AMC Consultants Pty Limited, Golder Associates
Pty Limited, Ausenco Engineering Canada Inc. and Optiro Pty Limited respectively. Certificates of sign-off have been received from
the companies conducting the external reviews to state that the Mineral Resource and/or Ore Reserve comply with the SAMREC
and JORC Codes.
In addition, numerous internal Mineral Resource and Ore Reserve process reviews were completed by suitably qualified Competent
Persons from within AngloGold Ashanti and no significant deficiencies were identified. The Mineral Resource and Ore Reserve are
underpinned by appropriate Mineral Resource management processes and protocols that ensure adequate corporate governance.
These procedures have been developed to be compliant with the guiding principles of the Sarbanes-Oxley Act of 2002.
AngloGold Ashanti makes use of a web-based group reporting database called the Resource and Reserve Reporting System
(RCubed) for the compilation and authorisation of Mineral Resource and Ore Reserve reporting. It is a fully integrated system for the
reporting and reconciliation of Mineral Resource and Ore Reserve that supports various regulatory reporting requirements including
the SEC and the JSE under SAMREC. AngloGold Ashanti uses RCubed to ensure a documented chain of responsibility exists from
the Competent Persons at the operations to the company’s RRSC.
AngloGold Ashanti has also developed an enterprise-wide risk management tool that provides consistent and reliable data that
allows for visibility of risks and actions across the group. This tool is used to facilitate, control and monitor material risks to the
Mineral Resource and Ore Reserve, thus ensuring that the appropriate risk management and mitigation plans are in place.
4
SECTION 1 / INTRODUCTION
COMPETENT PERSONS
The information in this report relating to exploration results, Mineral Resource and Ore Reserve, is based on information compiled
by or under the supervision of the Competent Persons as defined in the SAMREC or JORC Codes. All Competent Persons are
employed by AngloGold Ashanti, except for Kibali and Morila, and have sufficient experience relevant to the style of mineralisation
and type of deposit under consideration and to the activity which they are undertaking. The legal tenure of each operation and
project has been verified to the satisfaction of the accountable Competent Person and all their Ore Reserve have been confirmed to
be covered by the required mining permits or there exists a realistic expectation that these permits will be issued. This information
is detailed within this report. The Competent Persons consent to the inclusion of Exploration Results, Mineral Resource and Ore
Reserve information in this report, in the form and context in which it appears.
Accordingly, the Chairman of the RRSC, VA Chamberlain, MSc (Mining Engineering), BSc (Hons) (Geology), MGSSA, FAusIMM,
assumes responsibility for the Mineral Resource and Ore Reserve processes for AngloGold Ashanti and is satisfied that the
Competent Persons have fulfilled their responsibilities. VA Chamberlain has 31 years’ experience in exploration and mining and is
employed full-time by AngloGold Ashanti and can be contacted at the following address: 76 Rahima Moosa Street, Newtown, 2001,
South Africa.
Ghana – Obuasi
5
SECTION 1 / INTRODUCTION
YEAR IN REVIEW
AngloGold Ashanti strives to actively create value by growing its major asset – the Mineral Resource
and Ore Reserve. This drive is based on active, well-defined brownfields and greenfields exploration
programmes, innovation in both geological modelling and mine planning and continual optimisation
of the asset portfolio.
and Ore Reserve. This drive is based on active, well-defined brownfields and greenfields exploration
programmes, innovation in both geological modelling and mine planning and continual optimisation
of the asset portfolio.
PRICE ASSUMPTIONS
The SAMREC code requires the use of reasonable economic assumptions. These include long-range commodity price and
exchange rate forecasts. These are reviewed annually and are prepared in-house using a range of techniques including historic
price averages.
The Mineral Resource sensitivities shown in the detail of this report use a base of $1,400/oz and a range of $200/oz, unless
otherwise stated.
Gold price
The following local prices of gold were used as the basis for estimation:
Gold price
US$/oz
Local prices of gold
South Africa
ZAR/kg
Australia
AUD/oz
Brazil
BRL/oz
Argentina
ARS/oz
2018 Ore Reserve
1,100
501,150
1,509
3,565
45,443
2017 Ore Reserve
1,100
512,059
1,491
3,573
17,898
2018 Mineral Resource
1,400
563,331
1,778
4,501
51,564
2017 Mineral Resource
1,400
601,870
1,824
4,492
21,242
Copper price
The following copper prices were used as the basis for estimation:
Copper price
US$/lb
2018 Ore Reserve
2.65
2018 Mineral Resource
3.30
2017 Mineral Resource
3.16
MINERAL RESOURCE
Gold
The AngloGold Ashanti Mineral Resource reduced from 208.2Moz in December 2017 to 184.5Moz in December 2018. This gross
annual decrease of 23.7Moz includes depletion of 4.0Moz and the disposal of assets of 20.1Moz. The balance of 0.4Moz results
from increases due to exploration and modelling of 4.5Moz and other factors of 0.1Moz and reductions due to revised geotechnical
design requirements of 4.0Moz and changes in cost of 0.2Moz. The Mineral Resource was estimated at a gold price of US$1,400/oz
(2017: US$1,400/oz).
6
SECTION 1 / INTRODUCTION
Year-on-year changes
Moz
Mineral Resource as at 31 December 2017
208.2
Disposals
Moab Khotsong
(16.2)
Kopanang
(3.0)
Vaal River Surface
(0.9)
Sub-total
188.1
Depletions
(4.0)
Sub-total
184.1
Additions
AGA Mineração
Increase due to exploration and modelling revisions
0.6
Kibali
Exploration success resulted in the increase in Mineral Resource
0.6
Cerro Vanguardia
The increase is due to a combination of reduced costs and revised
estimation methodology
0.5
Other
Additions less than 0.5Moz
2.3
Sub-total
188.1
Reductions
Mponeng
The key reason for the reduction was the removal of the TauTona
shaft pillars and increased costs. These reductions were countered
in part by drilling success
(3.5)
Other
Reductions less than 0.5Moz
(0.1)
Mineral Resource as at 31 December 2018
184.5
Copper
The AngloGold Ashanti Mineral Resource reduced from 3.63Mt (8,000Mlbs) in December 2017 to 3.61Mt (7,954Mlbs) in December
2018. This gross annual decrease of 0.02Mt includes a reduction due to methodology of 0.09Mt offset by a change in ownership
of 0.05Mt and other factors which resulted in an increase of 0.02Mt. The Mineral Resource was estimated at a copper price of
US$3.30/lb (2017: US$3.16/lb).
Year-on-year changes
7
SECTION 1 / INTRODUCTION
YEAR IN REVIEW CONTINUED
Mt
Mlb
Mineral Resource as at 31 December 2017
3.63
8,000
Reductions
Quebradona
(0.02)
(46)
Mineral Resource as at 31 December 2018
3.61
7,954
ORE RESERVE
Gold
The AngloGold Ashanti Ore Reserve reduced from 49.5Moz in December 2017 to 44.1Moz in December 2018. This gross annual
decrease of 5.4Moz includes depletion of 3.6Moz. The loss after depletions of 1.8Moz, results from the disposal of assets in the
South African region of 6.1Moz, additions due to exploration and modelling changes of 4.3Moz, whilst other factors resulted in a
0.1Moz addition and changes in economic assumptions resulted in a 0.1Moz reduction. The Ore Reserve was estimated using a
gold price of US$1,100/oz (2017: US$1,100/oz).
Year-on-year changes
Moz
Ore Reserve as at 31 December 2017
49.5
Disposals
Moab Khotsong
(4.8)
Kopanang
(0.3)
Vaal River Surface
(0.9)
Sub-total
43.5
Depletions
(3.6)
Sub-total
39.9
Additions
Quebradona
Initial Ore Reserve publication post successful conclusion of the
prefeasibility study
2.2
Geita
Additions are primarily due to exploration success on underground
targets at Star and Comet and Nyankanga
0.5
CVSA
Reduced cost and exploration success led to the additions
0.4
Sunrise Dam
The increase is due to exploration success
0.3
Other
Additions less than 0.3Moz
1.1
Sub-total
44.4
Reductions
Other
Reductions less than 0.3Moz
(0.3)
Ore Reserve as at 31 December 2018
44.1
Copper
The maiden AngloGold Ashanti Ore Reserve for copper of 1.26Mt (2,769Mlbs) is based on exploration success and the completion
8
SECTION 1 / INTRODUCTION
of the prefeasibility study (PFS) at Quebradona. The Ore Reserve was estimated at a copper price of US$2.65/lb.
Year-on-year changes
Mt
Mlb
Ore Reserve as at 31 December 2017
0.00
0
Additions
Quebradona
Exploration success and completion of the PFS
1.26
2,769
Ore Reserve as at 31 December 2018
1.26
2,769
SALE OF ASSETS
AngloGold Ashanti sold various assets in the Vaal River region of its South African operations. The sales processes were finalised
9
SECTION 1 / INTRODUCTION
YEAR IN REVIEW CONTINUED
on 28 February 2018. On conclusion of the sales and after depletions for that period of 2018, the final Mineral Resource and Ore
Reserve at the time of the sale are shown below:
Operation
Category
Moz
Kopanang
Mineral Resource
3.00
Ore Reserve
0.35
Moab Khotsong
Mineral Resource
16.20
Ore Reserve
4.83
Surface Operations
Mineral Resource
0.87
Ore Reserve
0.87
BY-PRODUCTS
Several by-products will be recovered as a result of processing of the gold Ore Reserve and copper Ore Reserve. These include
0.37Mt of sulphur from Brazil, 32.68Moz of silver from Argentina and 23.58Moz of silver from Colombia.
Brazil – AGA Mineração – Cuiabá
10
SECTION 1 / INTRODUCTION
Mineral Resource by country (attributable) inclusive of Ore Reserve: gold
as at 31 December 2018
Category
Tonnes
million
Grade
g/t
Contained gold
tonnes
Moz
South Africa
Measured
113.47
1.49
168.68
5.42
Indicated
614.07
1.91
1,170.36
37.63
Inferred
29.10
9.35
271.96
8.74
Total
756.64
2.13
1,611.00
51.79
Democratic Republic of the Congo
Measured
9.17
4.60
42.16
1.36
Indicated
44.71
3.05
136.37
4.38
Inferred
23.77
2.50
59.40
1.91
Total
77.65
3.06
237.93
7.65
Ghana
Measured
6.84
3.27
22.35
0.72
Indicated
184.26
4.08
750.93
24.14
Inferred
77.77
5.90
458.67
14.75
Total
268.87
4.58
1,231.95
39.61
Guinea
Measured
20.36
0.63
12.89
0.41
Indicated
164.46
0.87
143.58
4.62
Inferred
71.93
0.93
66.84
2.15
Total
256.75
0.87
223.30
7.18
Mali
Measured
4.86
0.54
2.62
0.08
Indicated
48.39
1.82
88.27
2.84
Inferred
7.23
1.68
12.19
0.39
Total
60.48
1.70
103.07
3.31
Tanzania
Measured
0.94
6.29
5.92
0.19
Indicated
28.11
3.22
90.57
2.91
Inferred
21.81
4.50
98.20
3.16
Total
50.86
3.83
194.69
6.26
Australia
Measured
59.03
1.48
87.32
2.81
Indicated
90.51
1.98
179.38
5.77
Inferred
29.79
2.77
82.52
2.65
Total
179.34
1.95
349.22
11.23
Argentina
Measured
9.37
2.14
20.00
0.64
Indicated
20.95
2.75
57.53
1.85
Inferred
4.61
2.45
11.31
0.36
Total
34.93
2.54
88.85
2.86
Brazil
Measured
20.97
6.45
135.29
4.35
Indicated
24.20
5.83
141.02
4.53
Inferred
45.59
5.86
267.05
8.59
Total
90.76
5.99
543.36
17.47
Colombia
Measured
–
–
–
–
Indicated
1,158.98
0.77
896.67
28.83
Inferred
607.13
0.43
258.50
8.31
Total
1,766.10
0.65
1,155.17
37.14
Total
Measured
245.01
2.03
497.23
15.99
Indicated
2,378.65
1.54
3,654.68
117.50
Inferred
918.73
1.73
1,586.64
51.02
Total
3,542.39
1.62
5,738.55
184.50
GROUP OVERVIEW
11
SECTION 1 / INTRODUCTION
GROUP OVERVIEW CONTINUED
Mineral Resource by country (attributable) exclusive of Ore Reserve: gold
as at 31 December 2018
Category
Tonnes
million
Grade
g/t
Contained gold
tonnes
Moz
South Africa
Measured
6.64
19.83
131.75
4.24
Indicated
30.97
17.42
539.39
17.34
Inferred
10.62
13.88
147.43
4.74
Total
48.24
16.97
818.56
26.32
Democratic Republic of the Congo
Measured
1.42
2.68
3.81
0.12
Indicated
22.68
2.43
55.11
1.77
Inferred
23.77
2.50
59.40
1.91
Total
47.87
2.47
118.32
3.80
Ghana
Measured
3.51
5.57
19.55
0.63
Indicated
131.17
3.95
517.50
16.64
Inferred
75.01
6.09
456.79
14.69
Total
209.69
4.74
993.84
31.95
Guinea
Measured
–
–
–
–
Indicated
97.67
0.87
85.03
2.73
Inferred
71.93
0.93
66.84
2.15
Total
169.60
0.90
151.87
4.88
Mali
Measured
–
–
–
–
Indicated
21.08
1.72
36.21
1.16
Inferred
7.23
1.68
12.19
0.39
Total
28.32
1.71
48.40
1.56
Tanzania
Measured
0.11
9.89
1.13
0.04
Indicated
19.45
2.77
53.85
1.73
Inferred
21.81
4.50
98.20
3.16
Total
41.37
3.70
153.19
4.93
Australia
Measured
32.57
1.65
53.73
1.73
Indicated
52.76
1.78
93.66
3.01
Inferred
27.46
2.70
74.14
2.38
Total
112.78
1.96
221.53
7.12
Argentina
Measured
1.58
1.27
2.01
0.06
Indicated
12.54
3.34
41.88
1.35
Inferred
3.28
2.97
9.75
0.31
Total
17.41
3.08
53.64
1.72
Brazil
Measured
15.71
6.50
102.11
3.28
Indicated
13.87
4.63
64.25
2.07
Inferred
44.14
5.92
261.47
8.41
Total
73.73
5.80
427.82
13.75
Colombia
Measured
–
–
–
–
Indicated
991.22
0.78
772.88
24.85
Inferred
607.13
0.43
258.50
8.31
Total
1,598.34
0.65
1,031.38
33.16
Total
Measured
61.56
5.10
314.09
10.10
Indicated
1,393.41
1.62
2,259.75
72.65
Inferred
892.38
1.62
1,444.71
46.45
Total
2,347.35
1.71
4,018.55
129.20
12
SECTION 1 / INTRODUCTION
Mineral Resource by country (attributable) inclusive of Ore Reserve: copper
as at 31 December 2018
Category
Tonnes
million
Grade
%Cu
Contained copper
tonnes million pounds million
Colombia
Measured
–
–
–
–
Indicated
242.57
0.86
2.09
4,617
Inferred
325.40
0.47
1.51
3,337
Total
567.97
0.64
3.61
7,954
Total
Measured
–
–
–
–
Indicated
242.57
0.86
2.09
4,617
Inferred
325.40
0.47
1.51
3,337
Total
567.97
0.64
3.61
7,954
Mineral Resource by country (attributable) exclusive of Ore Reserve: copper
as at 31 December 2018
Category
Tonnes
million
Grade
%Cu
Contained copper
tonnes million pounds million
Colombia
Measured
–
–
–
–
Indicated
138.52
0.61
0.84
1,848
Inferred
325.40
0.47
1.51
3,337
Total
463.92
0.51
2.35
5,185
Total
Measured
–
–
–
–
Indicated
138.52
0.61
0.84
1,848
Inferred
325.40
0.47
1.51
3,337
Total
463.92
0.51
2.35
5,185
Ghana – Iduapriem
13
SECTION 1 / INTRODUCTION
Ore Reserve by country (attributable): gold
as at 31 December 2018
Category
Tonnes
million
Grade
g/t
Contained gold
tonnes
Moz
South Africa
Proved
107.67
0.31
33.89
1.09
Probable
564.02
0.87
488.59
15.71
Total
671.70
0.78
522.47
16.80
Democratic Republic of the Congo
Proved
9.14
4.15
37.87
1.22
Probable
19.08
4.12
78.70
2.53
Total
28.22
4.13
116.57
3.75
Ghana
Proved
2.74
0.88
2.41
0.08
Probable
56.66
4.07
230.82
7.42
Total
59.40
3.93
233.23
7.50
Guinea
Proved
21.54
0.67
14.40
0.46
Probable
59.40
0.84
49.82
1.60
Total
80.94
0.79
64.22
2.06
Mali
Proved
2.50
0.65
1.62
0.05
Probable
26.27
1.94
50.86
1.64
Total
28.78
1.82
52.48
1.69
Tanzania
Proved
–
–
–
–
Probable
9.47
4.38
41.49
1.33
Total
9.47
4.38
41.49
1.33
Australia
Proved
26.43
1.27
33.50
1.08
Probable
37.63
2.27
85.26
2.74
Total
64.06
1.85
118.76
3.82
Argentina
Proved
7.72
2.32
17.88
0.57
Probable
8.14
1.89
15.41
0.50
Total
15.86
2.10
33.30
1.07
Brazil
Proved
3.52
3.70
13.01
0.42
Probable
11.04
4.71
51.94
1.67
Total
14.56
4.46
64.95
2.09
Colombia
Proved
–
–
–
–
Probable
167.76
0.74
123.79
3.98
Total
167.76
0.74
123.79
3.98
Total
Proved
181.26
0.85
154.60
4.97
Probable
959.49
1.27
1,216.69
39.12
Total
1,140.75
1.20
1,371.28
44.09
Ore Reserve by country (attributable): copper
as at 31 December 2018
Category
Tonnes
million
Grade
%Cu
Contained copper
tonnes million pounds million
Colombia
Proved
–
–
–
–
Probable
104.05
1.21
1.26
2,769
Total
104.05
1.21
1.26
2,769
Total
Proved
–
–
–
–
Probable
104.05
1.21
1.26
2,769
Total
104.05
1.21
1.26
2,769
GROUP OVERVIEW CONTINUED
14
SECTION 1 / INTRODUCTION
Australia – Tropicana
15
SECTION 1 / INTRODUCTION
GROUP OVERVIEW CONTINUED
Reconciliation of inclusive Mineral Resource (gold content Moz)
as at 31 December 2018
Previous
year
Depletion
Explora-
tion
Metho-
dology
Gold
price
price
Cost
Geo-
technical
Metal-
lurgical
Other
Acquisition/
disposal
South Africa region
Kopanang
3.02
(0.02)
–
–
–
–
–
–
–
(3.01)
Moab Khotsong
16.30
(0.05)
–
–
–
–
–
–
–
(16.25)
Vaal River Surface
3.68
(0.19)
(0.00)
–
–
–
0.01
–
0.18
(0.87)
Mine Waste Solutions
2.24
(0.07)
–
–
–
–
–
–
0.00
–
West Wits Surface
0.67
(0.04)
–
–
–
–
0.00
–
(0.01)
–
Mponeng
49.97
(0.32)
0.49
–
–
(0.43)
(3.31)
–
(0.22)
–
Total
75.89
(0.69)
0.49
–
–
(0.43)
( 3.29)
–
(0.05)
(20.13)
Continental Africa region
Kibali
7.44
(0.36)
0.61
(0.00)
–
(0.01)
–
–
(0.04)
–
Iduapriem
5.54
(0.36)
0.04
–
–
0.34
–
–
(0.00)
–
Obuasi
34.05
–
–
–
–
–
–
–
–
–
Siguiri
7.27
(0.30)
0.06
0.01
–
0.13
–
0.02
–
–
Morila
0.11
(0.05)
0.03
(0.01)
–
–
–
–
(0.00)
–
Sadiola
3.29
(0.06)
–
–
–
–
–
–
(0.00)
–
Geita
6.42
(0.61)
0.22
0.20
–
0.01
–
–
0.02
–
Total
64.13
(1.75)
0.96
0.20
–
0.46
–
0.02
(0.02)
–
Australasia region
Sunrise Dam
5.98
(0.30)
0.69
0.39
–
(0.35)
(0.58)
–
–
–
Tropicana
5.22
(0.33)
0.91
(0.04)
–
(0.35)
–
–
(0.02)
–
Total
11.20
(0.62)
1.60
0.35
–
(0.70)
(0.58)
–
(0.02)
–
Americas region
Cerro Vanguardia
2.64
(0.29)
0.05
0.15
–
0.36
–
–
(0.07)
–
AGA Mineração
13.57
(0.52)
(0.10)
0.66
–
0.15
(0.13)
–
–
–
Serra Grande
3.66
(0.15)
0.16
0.20
–
(0.05)
–
–
0.01
–
Gramalote
3.07
–
–
–
–
–
–
–
–
–
La Colosa
28.33
–
–
–
–
–
–
–
–
–
Quebradona
5.66
–
–
(0.25)
–
–
–
–
0.24
0.08
Total
56.94
(0.95)
0.11
0.76
–
0.47
(0.13)
–
0.19
0.08
Grand total
208.16
(4.01)
3.16
1.31
–
(0.20)
(4.00)
0.02
0.10
(20.04)
Reconciliation of inclusive Mineral Resource (copper content Mlb)
as at 31 December 2018
Previous
year
Depletion
Explora-
tion
Metho-
dology
Gold
price
price
Cost
Geo-
technical
Metal-
lurgical
Other
Acquisition/
Disposal
Americas region
Quebradona
8,000
–
–
(205)
–
–
–
–
42
117
Total
8,000
–
–
(205)
–
–
–
–
42
117
Grand total
8,000
–
–
(205)
–
–
–
–
42
117
16
SECTION 1 / INTRODUCTION
Current
year
Net diff
%
Comments
–
(3.02)
(100)
Asset sold to Village Main Reef (VMR) in February 2018.
–
(16.30)
(100)
Asset sold to Harmony Gold in February 2018.
2.81
(0.87)
(24)
Changes are mainly due to the Harmony sale of Mispah 1 and 2 tailing storage facilities (TSFs) and Kopanang Paydam.
Annual depletions from Sulphur Paydam, East TSF and South East Extension.
Annual depletions from Sulphur Paydam, East TSF and South East Extension.
2.18
(0.07)
(3)
Normal depletions from Harties 1 & 2 TSFs. Evaluation model grade adjustment for Harties 1 done on remainder of material.
0.62
(0.05)
(7)
Normal depletions from Mponeng and Savuka low grade stockpiles and Old North TSF.
46.18
(3.79)
(8)
The TauTona and Savuka shaft pillars have been removed as they will not be included in the LOM plan. Further reductions
included depletions and an increase in the required mining grade based on the current cost of extraction.
included depletions and an increase in the required mining grade based on the current cost of extraction.
51.79
(24.10)
(32)
7.65
0.21
3
Kibali was able to replace Mineral Resource ounces depleted as a result of the maiden reporting of the Kalimva and Ikamva
open pit Inferred Mineral Resource, as well as exploration extensions in KCD undergound.
open pit Inferred Mineral Resource, as well as exploration extensions in KCD undergound.
5.56
0.02
0
Year-on-year changes include a decrease to the Mineral Resource as a result of depletion and increases as a result of
exploration drilling and cost reductions.
exploration drilling and cost reductions.
34.05
–
–
The Mineral Resource remains the same as 2017 as no mining took place in 2018.
7.18
(0.10)
(1)
Depletion was offset by gains due to reduced cost which brought back Eureka North, and exploration infill drilling at Foulata,
Saraya and Silakoro and metallurgical improvements due to the introduction of the CIL option for Foulata and Saraya.
Saraya and Silakoro and metallurgical improvements due to the introduction of the CIL option for Foulata and Saraya.
0.09
(0.02)
(22)
Depletions have been partially offset by the addition of Viper and Ntiola open pits from exploration.
3.23
(0.06)
(2)
Mainly due to mining depletions.
6.26
(0.16)
(3)
Depletion was offset by a gain largely from conversion of Inferred to Indicated Mineral Resource and exploration gain due to
new drilling information for underground projects and a slight impact from lower cut-off grades in comparison to the previous
year.
new drilling information for underground projects and a slight impact from lower cut-off grades in comparison to the previous
year.
64.01
(0.12)
(0)
5.84
(0.14)
(2)
Exploration activities centred around the Vogue domain resulted in Mineral Resource additions. These were offset by
Mineral Resource write-off of unmineable pillars and skins of historic stopes. Increases in year-on-year costs resulted in a
further decrease.
Mineral Resource write-off of unmineable pillars and skins of historic stopes. Increases in year-on-year costs resulted in a
further decrease.
5.39
0.17
3
Addition through exploration success at Boston Shaker underground offset by depletion. Havana South underground
Mineral Resource adjusted in-line with updated Mineral Resource shell optimisation.
Mineral Resource adjusted in-line with updated Mineral Resource shell optimisation.
11.23
0.03
0
2.86
0.21
8
Year-on-year changes are due to depletion offset by positive changes due to methodology and costs.
13.63
0.06
0
The Lamego Mineral Resource increased mainly due to the update of cut-off with the new exchange rate and costs offset
by depletion and methodology changes. The Cuiabá Mineral Resource increased mainly due to new sampling information
and refining of the model to exclude internal waste offset by deletions. The CdS Mineral Resource reduced mainly due to
depletions, new information and an increase in costs for open pit mining offset by estimation methodology changes.
by depletion and methodology changes. The Cuiabá Mineral Resource increased mainly due to new sampling information
and refining of the model to exclude internal waste offset by deletions. The CdS Mineral Resource reduced mainly due to
depletions, new information and an increase in costs for open pit mining offset by estimation methodology changes.
3.84
0.17
5
The depletion was replaced by exploration and revised methodology.
3.07
–
–
No change from 2017.
28.33
–
–
No material change from 2017.
5.74
0.08
1
Minor changes due to updated Mineable Shape Optimiser (MSO) analysis. Main changes to the Indicated/Inferred Mineral
Resource resulting from classification update using conditional simulation and kriging variance approach.
Resource resulting from classification update using conditional simulation and kriging variance approach.
57.47
0.53
1
184.50
(23.66)
(11)
Current
year
Net diff
%
Comments
7,954
(46)
(1)
Minor changes due to updated MSO analysis. Main changes to the Indicated/Inferred Mineral Resource resulting
from classification update using conditional simulation and kriging variance approach.
from classification update using conditional simulation and kriging variance approach.
7,954
(46)
(1)
7,954
(46)
(1)
17
SECTION 1 / INTRODUCTION
GROUP OVERVIEW CONTINUED
Reconciliation of Ore Reserve (gold content Moz)
as at 31 December 2018
Previous
year
Depletion
Explora-
tion
Metho-
dology
Gold
price
price
Cost
Geo-
technical
Metal-
lurgical
Revenue
factor
Other
South Africa region
Kopanang
0.36
(0.01)
–
–
–
–
–
–
–
–
Moab Khotsong
4.87
(0.04)
–
–
–
–
–
–
–
–
Vaal River Surface
3.68
(0.17)
(0.00)
–
–
–
0.01
–
–
0.01
Mine Waste Solutions
2.24
(0.08)
0.01
–
–
–
–
–
–
0.00
West Wits Surface
0.19
(0.03)
–
0.16
–
–
0.00
(0.00)
–
(0.00)
Mponeng
12.16
(0.27)
0.26
(0.02)
–
–
(0.28)
–
–
(0.20)
Total
23.51
(0.60)
0.27
0.14
–
–
(0.26)
(0.00)
–
(0.19)
Continental Africa region
Kibali
3.91
(0.44)
0.20
–
–
0.02
–
–
–
0.06
Iduapriem
1.85
(0.33)
–
–
–
0.04
( 0.01)
–
–
0.08
Obuasi
5.86
–
–
–
–
–
–
–
–
–
Siguiri
2.24
(0.24)
0.03
–
–
0.07
0.02
–
(0.00)
(0.06)
Morila
0.08
(0.04)
0.02
(0.00)
–
–
0.00
–
–
(0.00)
Sadiola
1.70
(0.05)
–
–
–
–
–
–
–
(0.02)
Geita
1.25
(0.44)
0.45
–
–
(0.00)
–
–
0.02
0.05
Total
16.89
(1.54)
0.71
(0.00)
–
0.13
0.01
–
0.02
0.11
Australasia region
Sunrise Dam
1.19
(0.33)
0.25
–
–
0.04
0.02
–
–
0.03
Tropicana
2.85
(0.31)
0.22
(0.00)
0.00
(0.47)
–
0.00
–
0.31
Total
4.05
(0.64)
0.47
(0.00)
0.00
(0.43)
0.02
0.00
–
0.34
Americas region
CVSA
0.91
(0.28)
0.19
0.19
–
0.12
(0.06)
–
–
–
AGA Mineração
2.06
(0.40)
(0.04)
(0.01)
0.00
0.02
0.04
0.00
–
0.03
Serra Grande
0.33
(0.14)
–
0.15
(0.00)
0.07
0.01
–
(0.01)
(0.02)
Gramalote
1.76
–
–
–
–
–
–
–
–
–
Quebradona
–
–
2.22
–
–
–
–
–
–
–
Total
5.06
(0.82)
2.37
0.33
0.00
0.21
(0.01)
0.00
(0.01)
0.01
Grand total
49.51
(3.60)
3.81
0.46
0.00
(0.08)
(0.24)
0.00
0.01
0.27
Reconciliation of Ore Reserve (copper content Mlb)
as at 31 December 2018
Previous
year
Depletion
Explora-
tion
Metho-
dology
Gold
price
price
Cost
Geo-
technical
Metal-
lurgical
Revenue
factor
Other
Americas region
Quebradona
–
–
2,769
–
–
–
–
–
–
–
Total
–
–
2,769
–
–
–
–
–
–
–
Grand total
–
–
2,769
–
–
–
–
–
–
–
18
SECTION 1 / INTRODUCTION
Acquisition/
disposal
Current
year
Net diff
%
Comments
(0.35)
–
(0.36)
(100)
Asset sold to VMR mining company in February 2018.
(4.83)
–
(4.87)
(100)
Asset sold to Harmony Gold mining company in February 2018.
(0.87)
2.65
(1.03)
(28)
Significant portion sold to Harmony (Mispah 1 and Kopanang TSF as well as Moab Khotsong low
grade stockpile). Normal depletion from tailings material as well as No. 5 low grade stockpile.
grade stockpile). Normal depletion from tailings material as well as No. 5 low grade stockpile.
–
2.18
(0.07)
(3)
Normal depletions from tailings material through Mine Waste Solutions (MWS) plant.
–
0.33
0.13
69
Normal depletions from Mponeng and Savuka low grade stockpiles as well as Old North TSF.
–
11.65
(0.52)
(4)
Mponeng Ore Reserve decreased from the previous period mainly due to depletions and the removal
of the TauTona shaft pillar Ore Reserve post the closure of the TauTona new technology project.
of the TauTona shaft pillar Ore Reserve post the closure of the TauTona new technology project.
(6.06)
16.80
(6.71)
(29)
–
3.75
(0.16)
(4)
The Ore Reserve decreased year-on-year, mainly due to depletion, partially offset by exploration
success in the underground and conversion drilling in the KCD open pit.
success in the underground and conversion drilling in the KCD open pit.
–
1.63
(0.22)
(12)
Minor cost improvements failed to replace dilution.
–
5.86
–
–
No mining or redesign occurred in 2018 as the mine remained on care and maintenance. The Ore
Reserve figure remains as it was in 2017.
Reserve figure remains as it was in 2017.
–
2.06
(0.18)
(8)
Positive model changes from infill drilling in Silakoro and Seguélén, decrease in costs mainly due
to general and administration, increased slope angle in Bidini and Tubani (Sorofe) and changes in
stockpile inventories failed to cover the depletion.
to general and administration, increased slope angle in Bidini and Tubani (Sorofe) and changes in
stockpile inventories failed to cover the depletion.
–
0.06
(0.02)
(26)
Depletions were partially offset by the addition of Viper and Ntiola open pits from exploration.
–
1.63
(0.07)
(4)
Mainly due to depletions and the exclusion of Tambali and FE3 pits.
–
1.33
0.08
7
Driven primarily by depletions offset by the introduction of Nyankanga Block 4 underground
Ore Reserve.
Ore Reserve.
–
16.33
(0.56)
(3)
–
1.20
0.01
1
The major change to the Ore Reserve was depletion, which was largely offset by additions in Vogue.
–
2.62
(0.24)
(8)
The majority of the Ore Reserve change for Tropicana gold mine is due to depletion. Other
changes due to cost are balanced by exploration and the addition of Boston Shaker underground.
changes due to cost are balanced by exploration and the addition of Boston Shaker underground.
–
3.82
(0.23)
(6)
–
1.07
0.16
18
Exploration and changes to the estimation methodology more than replaced the depletion.
–
1.70
(0.36)
(17)
The Lamego Ore Reserve reduced mainly due to mining depletion offset by exploration success
coming from the Carruagem and Queimada orebodies and costs. The Cuiabá Ore Reserve
reduced mainly due to mining depletions. The CdS Ore Reserve reduced mainly due to depletions
and the inclusion of transitional and sulphide material in the CdS Rosalino open pit as well as
Mineral Resource conversions.
coming from the Carruagem and Queimada orebodies and costs. The Cuiabá Ore Reserve
reduced mainly due to mining depletions. The CdS Ore Reserve reduced mainly due to depletions
and the inclusion of transitional and sulphide material in the CdS Rosalino open pit as well as
Mineral Resource conversions.
–
0.39
0.06
17
The main negative impacts were due to exchange ratio (lower gold price and higher
cost). The main positive impacts were model change and scope change (geotechnical).
cost). The main positive impacts were model change and scope change (geotechnical).
–
1.76
–
–
The Ore Reserve remains the same as 2017.
–
2.22
2.22
–
Maiden Ore Reserve declaration based on exploration success and the completion of the PFS.
–
7.14
2.08
41
(6.06)
44.09
(5.42)
(11)
Acquisition/
Disposal
Current
year
Net diff
%
Comments
–
2,769
2,769
100
Maiden Ore Reserve declaration based on exploration success and the completion of the PFS.
–
2,769
2,769
100
–
2,769
2,769
100
19
SECTION 1 / INTRODUCTION
SOUTH AFRICA
CONTENTS
Regional overview
21
Mponeng
24
Surface Operations
36
Pretoria
LEGEND
1
West Wits operations
Includes Mponeng
and West Wits Surface
Operations
2
Vaal River operations
Includes MWS and
Vaal River Surface
Operations
CONTENTS
Regional overview
21
Mponeng
24
Surface Operations
36
South Africa – Mponeng
20
SECTION 2 / SOUTH AFRICA
REGIONAL OVERVIEW
Key statistics
Units
2018
2017
2016
Operational performance
Tonnes treated/milled
Mt
34.9
38.9
39.6
Recovered grade
(1)
oz/t
0.219
0.202
0.219
g/t
6.82
6.93
7.51
Gold production
000oz
487
903
967
Total cash costs
$/oz
1,033
1,085
896
Total production costs
$/oz
1,187
1,247
1,089
All-in sustaining costs
(2)
$/oz
1,178
1,245
1,081
Capital expenditure
$m
73
150
182
(1)
Refers to underground operations only
(2)
Excludes stockpile write-offs
As at December 2018, AngloGold Ashanti’s operations in South Africa had a total Mineral Resource (inclusive
of the Ore Reserve) of 51.8Moz (2017: 75.9Moz) and an Ore Reserve of 16.8Moz (2017: 23.5Moz).
of the Ore Reserve) of 51.8Moz (2017: 75.9Moz) and an Ore Reserve of 16.8Moz (2017: 23.5Moz).
This is equivalent to 28% and 38% of the group’s Mineral Resource and Ore Reserve respectively. The South African operations
produced 487koz of gold in 2018, or 14% of group production.
AngloGold Ashanti’s South Africa operations comprise one deep level underground mine and three surface processing operations,
collectively referred to as Surface Operations.
The underground mine, Mponeng is 100% owned by AngloGold Ashanti. Mponeng is situated near the town of Carletonville and
is included as part of the West Wits operation. The primary reef being mined is the Ventersdorp Contact Reef (VCR). The Carbon
Leader Reef (CLR) that was historically mined at the now closed TauTona mine, is planned to be mined in the Mponeng life of mine
(LOM) extension project. A sequential grid mining method is employed to extract the gold from the deep, narrow, tabular orebody.
The grid is pre-developed through a series of haulages and crosscuts. Stoping takes place by means of breast mining using
conventional hand held drill and blast techniques. The selective mining unit (SMU) is 100 x 100m.
21
SECTION 2 / SOUTH AFRICA
REGIONAL OVERVIEW CONTINUED
The Surface Operations are located in both the Vaal River and West Wits Operations and include the Vaal River Surface, Mine Waste
Solutions (MWS) and the West Wits Surface processing operations. They rework the low grade stockpiles and retreat the TSFs
which resulted from the mining and processing of the primary and secondary reef horizons.
Sale of assets
AngloGold Ashanti sold various assets in the Vaal River region of its South African operations. The sales processes were finalised
on 28 February 2018. On conclusion of the sales and after depletions for that period of 2018, the final Mineral Resource and
Ore Reserve at the time of the sale are shown below:
Operation
Category
Moz
Kopanang
Mineral Resource
3.00
Ore Reserve
0.36
Moab Khotsong
Mineral Resource
16.20
Ore Reserve
4.87
Surface Operations
Mineral Resource
0.87
Ore Reserve
0.87
Inclusive Mineral Resource
as at 31 December 2018
Category
Tonnes
million
Grade
g/t
Contained gold
tonnes
Moz
South Africa
Measured
113.47
1.49
168.68
5.42
Indicated
614.07
1.91
1,170.36
37.63
Inferred
29.10
9.35
271.96
8.74
Total
756.64
2.13
1,611.00
51.79
Exclusive Mineral Resource
as at 31 December 2018
Category
Tonnes
million
Grade
g/t
Contained gold
tonnes
Moz
South Africa
Measured
6.64
19.83
131.75
4.24
Indicated
30.97
17.42
539.39
17.34
Inferred
10.62
13.88
147.43
4.74
Total
48.24
16.97
818.56
26.32
Ore Reserve
as at 31 December 2018
Category
Tonnes
million
Grade
g/t
Contained gold
tonnes
Moz
South Africa
Proved
107.67
0.31
33.89
1.09
Probable
564.02
0.87
488.59
15.71
Total
671.70
0.78
522.47
16.80
22
SECTION 2 / SOUTH AFRICA
South Africa – Mine Waste Solutions
23
SECTION 2 / SOUTH AFRICA
MPONENG
INTRODUCTION
Property description
Mponeng Mine is a deep level gold mine operating between 3,160m and 3,740m below mine datum
(BMD) and is currently the deepest mine in the world with development at 3,841m BMD. Future
mining is planned to deepen the shaft bottom to 4,227m BMD. All production is currently from VCR
with future expansion planned on both VCR and the CLR horizons.
Location
The West Wits operations are a combination of Mponeng and the West Wits surface operations.
Mponeng is situated to the south of the town of Carletonville and is approximately 65km west of
Johannesburg.
History
Mponeng was previously known as the Western Deep Levels South Shaft, or No.1 Shaft. The
original twin shaft sinking from surface commenced in 1981 and was commissioned along with the
gold plant complex in 1986 when mining began. Production started through the use of two hoisting
shafts, a sub-shaft and two service shafts. The name changed to Mponeng Mine in 1999.
In 2017, Savuka and TauTona mines commenced orderly closure and the remaining TauTona Mineral
Resource and Ore Reserve are published as part of Mponeng Mine.
Legal aspects and tenure
AngloGold Ashanti holds the following mining right in the Mponeng area which has been successfully
converted, executed and registered as new order mining rights at the Mineral and Petroleum
Resource Titles Office (MPRTO).
•
GP30/5/1/2/2(01)MR valid from 14 February 2006 to 13 February 2036, covering 64.8km2
•
GP30/5/1/2/2(11)MR valid from 11 July 2006 to 1 July 2016, covering 0.3km2 (application for
extension pending)
•
GP30/5/1/2/2(248)MR valid from 16 October 2012 to 15 October 2022, covering 1.96km2
A S102 application was submitted in March 2017 to consolidate the 3 licences into a single mining
right (GP30/5/1/2/2(01)MR).
Mining method
For the exploitation of the ever deepening Mineral Resource and the need for exibility on a mine
of this nature, the sequential grid mining method was adopted. This has been proven as the best
method suited to safe deep level gold mining often associated with seismicity.
Operational infrastructure
Mponeng has its own processing plant situated adjacent to the mine. Ore and waste material is
hoisted separately with ore being delivered to the plant by means of a conveyor belt and the waste
rock going to the low grade stockpile.
Mineral processing
Ore mined is treated and smelted at the Mponeng gold plant, which also processes low grade ore
from the stockpile adjacent to the shaft.
The ore is initially ground down by means of semi-autogenous milling after which a conventional gold
leach process incorporating liquid oxygen injection is applied. The gold is then extracted by means
of carbon-in-pulp (CIP) technology.
The plant conducts electro-winning and smelting (induction furnaces).
Risks
Upgrading of the Mineral Resource confidence of the deeper parts of Mponeng continues to be
challenging. Surface exploration and underground exploration targets are slowly being completed
but access to ground ahead of the mining front is often limited. New information, once obtained,
does have the potential to affect the future of Mponeng Mine. Exploration drilling on the VCR at
depth is indicating that there might be an evolution of the current geological understanding. This will
be further quantified and understood as exploration work continues.
Seismicity, which is associated with ultra deep level mining, remains the most significant risk to the
execution of the mine plan. The risk is managed through ongoing seismic risk management, which
then informs the mining strategy and execution schedule.
24
SECTION 2 / SOUTH AFRICA
Map showing Mponeng Mine infrastructure and licences
Refer to the map showing Mponeng Mine infrastructure and licences on page 38.
VCR West Wits underground workings
Competent Persons
Responsibility
Competent Person
Professional
organisation
Membership
number
Relevant
experience
Qualification
Mineral Resource
Gareth Flitton
SACNASP
400019/15
15 years
BSc Hons (Geology), GDE
(Mineral Economics)
Ore Reserve
William Olivier
SAGC
MS 0136
28 years
GDE (Mining Engineering)
Measured Mineral Resource
Indicated Mineral Resource
Inferred Mineral Resource
Drill hole
Mining Rights area boundary
Development tunnels
Stoping
0
1,000
2,000
metres
25
SECTION 2 / SOUTH AFRICA
MPONENG CONTINUED
26
SECTION 2 / SOUTH AFRICA
GEOLOGY
Deposit type
The VCR is the main reef horizon mined at Mponeng Mine. The VCR forms the base of the Ventersdorp Supergroup, which caps
the Witwatersrand Supergroup through an angular unconformity. The overlying Ventersdorp Lavas halted the deposition of the VCR,
preserving it in its current state.
The VCR consists of a quartz pebble conglomerate, which can be up to 3m thick in places. The footwall stratigraphy, following
periods of uplift and erosion, controlled the development and preservation of the VCR, which is characterised by a series of channel
terraces preserved at different relative elevations, and the highest gold values are preserved in these channel deposits.
The different channel terraces are divided by zones of thinner slope reef, which are of lower value and become more prevalent on
the higher terraces and on the harder footwall units.
CLR West Wits underground workings
Measured Mineral Resource
Indicated Mineral Resource
Inferred Mineral Resource
Drill hole
Mining Rights area boundary
Development tunnels
Stoping
0
1,000
2,000
metres
27
SECTION 2 / SOUTH AFRICA
MPONENG CONTINUED
The relatively argillaceous protoquartzites of the Kimberley Formation in the central portion of Mponeng are covered by the best
preserved VCR conglomerates. The Elsburg Formation in the west is relatively more durable while the eastern side of the mine is
dominated by shales and siltstones of the Booysens Formation. No VCR is preserved on the Krugersdorp Formation on the far
eastern side of Mponeng.
The CLR is the other gold bearing reef reported as part of the total Mineral Resource for Mponeng. The CLR is located near the
base of the Johannesburg Subgroup, which forms part of the Central Rand Group of the Witwatersrand Supergroup of rocks.
The CLR and VCR at Mponeng Mine are separated by approximately 900m of shales and quartzites. The CLR has historically been
mined extensively at Savuka and TauTona mines and the remaining portions thereof have now been transferred to Mponeng Mine.
The CLR in the West Wits consists of, on average, a 20cm thick, tabular, auriferous quartz pebble conglomerate and three
sedimentary facies. Economically, the most important facies is Unit 1, which overlies Unit 2. Unit 1 is a complex channel deposit that
is only present along the eastern side of the West Wits lease area. Unit 2 can be up to 2m thick. Unit 3 is exposed in the southern
edges of the lease area and is the oldest of the conglomerates.
Mineralisation style
Gold mineralisation followed an episode of deep burial, fracturing and alteration. A variant of Archean gold bearing hydrothermal
fluid was introduced into the conglomerates and circulated throughout in hydrothermal cells. The fluids precipitated gold and other
elements through reactions that took place at elevated temperatures along the reef horizon, which was the more favourable fluid
conduit. In the case of the VCR, the resulting gold grades are mostly uniformly distributed throughout the reef package. In the CLR,
solid hydrocarbon precipitated in thin, at veins, usually at the base of the Carbon Leader conglomerate, and this is where the
majority of the gold is concentrated.
Mineralisation characteristics
The VCR displays strong alteration features, which can be explained by the hydrothermal fluids that infiltrated the reef and have
overprinted on the original mineral assemblage. Portions of the reef contain authigenic sulphides such as pyrite, pyrrhotite,
chalcopyrite, spahelerite and galena, incorporated in the conglomerate matrix. Gold associations with these mineral assemblages
indicate a strong correlation of gold mobilisation and redistribution at the time of the hydrothermal fluid influx. There is also a strong
association of gold with a chloritisation event focused along the reef horizon. The chlorite alteration gives a dark coloration to the reef.
Gold was precipitated by cooling and reactions between the fluids and wallrock, in this case pyritic conglomerates. Gold
mineralisation was enhanced in certain areas of high fluid throughput, which were often the sites of high carbon precipitation and
early alteration in the case of the CLR.
Both the VCR and the CLR have been subjected to faulting and are intruded by a series of igneous dykes and sills of various ages
that cross-cut the reefs. There is an inherent risk in mining through these faults and intrusives and a key objective of Mponeng Mine
geologists is to identify these geological features ahead of the working face to assist with deciding on the best way to approach and
mine through these structures.
EXPLORATION
Underground exploration in 2018 targeted the VCR areas to the west and down dip of the current mining on 123 and 126 Levels.
New reef intersections were achieved during 2018 and have been included in the evaluation of the geological model. No CLR
exploration was possible during 2018 due to the lack of suitable drill sites.
The new surface drill hole UD61A started delivering core in March 2018 and has reached a depth of 1,631m. The drill hole is
planned to intersect the VCR target at a depth of 3,850m. Progress on the UD63 surface drill hole was halted in 2018.
PROJECTS
28
SECTION 2 / SOUTH AFRICA
The Phase 1 VCR project is in production on 123 Level and is still accessing reef on 126 Level. On reef development continues east
and west and total production is expected to ramp up to 12,000m2 per month.
The Mponeng LOM extension project PFS was reviewed and approved to progress to feasibility study (FS) in February 2017.
The PFS determined that the best business case is achieved by accessing the CLR orebody as well as the VCR orebody below
current Mponeng infrastructure to 136 Level (4,138m BMD). The LOM extension project scope of work replaces the phased project
approach by combining the Phase 2 project with Phases 3 and 4 into one project to access 9.5Moz and to extend the LOM to
2048. The project infrastructure consists of a ramp to access the first three levels while the sub shafts are deepened to establish
permanent logistic infrastructure for the six new mining levels. The FS is in progress and the project proposal will be presented to
the Board in 2019.
MINERAL RESOURCEDETAIL OF AVERAGE DRILL HOLE SPACING AND TYPE IN RELATION TO MINERAL
RESOURCE CLASSIFICATION
RESOURCE CLASSIFICATION
Mineral Resource by-product: uranium
Legend
N-S Geological cross-section through Mponeng – SS1 shaft section, CLR deepening project
29
SECTION 2 / SOUTH AFRICA
MPONENG CONTINUED
30
SECTION 2 / SOUTH AFRICA
Estimation
Gold values have been shown to be intimately related to conglomerate preservation of the VCR and form an integral part of the
geological model, as does the footwall lithology.
Mixed support co-kriging is used in the estimation of the Mineral Resource. It is a technique that enables the use of data of mixed
support, allowing both drill hole and underground sampling data to be used together. Estimation is performed on the VCR into
large block sizes, generally >210 x 210m, which fully capture the within-block variance, allowing the co-kriging of data of different
support sizes over long ranges. Estimation is done per geological homogeneous zone, in logarithmic space, because of the highly
skewed gold distribution. The final gold estimates are then calculated by back transforming the estimates, using lognormal four
parameter distribution models. Simple kriging is used for grade control and Measured Mineral Resource at a 30 x 30m block size
and constrained by the weight of the mean value. A similar process is followed for the CLR estimation.
Exclusive Mineral Resource
as at 31 December 2018
Category
Tonnes
million
Grade
g/t
Contained gold
tonnes
Moz
Mponeng
Measured
6.64
19.83
131.75
4.24
Indicated
30.97
17.42
539.39
17.34
Inferred
10.62
13.88
147.43
4.74
Total
48.24
16.97
818.56
26.32
Current mining practice at the West Wits operations leaves behind a large portion of the Mineral Resource as stability pillars. Rock
engineering design models require stability to minimise the effects of mining induced seismicity on the deep underground workings.
Bracket pillars are also placed around all major geological structures to improve regional stability and to minimise the structure
associated risks. In future, the majority of the exclusive Mineral Resource will be taken up in stability pillars to reduce the impact of
seismicity. Other areas of the Mineral Resource that do not form part of the LOM include the areas between the Mineral Resource
and Ore Reserve cut-offs.
Mineral Resource below infrastructure
as at 31 December 2018
Category
Tonnes
million
Grade
g/t
Contained gold
tonnes
Moz
Mponeng
Measured
0.34
22.73
7.77
0.25
Indicated
40.54
19.03
771.46
24.80
Inferred
17.49
15.05
263.19
8.46
Total
58.38
17.86
1,042.42
33.51
The portion of the Mineral Resource below infrastructure included those in the VCR WUDLs and the CLR Mineral Resource area.
Mponeng Mine infrastructure has only been developed to access the orebody up to 126 Level on the VCR and 120 Level on
the CLR.
Grade tonnage curve
31
SECTION 2 / SOUTH AFRICA
MPONENG CONTINUED
Year-on-year, Mponeng’s published Mineral Resource has decreased. The Mineral Resource of the TauTona and Savuka shaft
pillars have been removed as they will not be included in the LOM plan due to geotechnical constraints. Further reductions included
depletions and an increase in the required mining grade based on the current cost of extraction. There was a slight increase in
estimated content due to updates of the model methodology on the back of data updates.
Year-on-year changes in Mineral Resource
32
SECTION 2 / SOUTH AFRICA
ORE RESERVE
Ore Reserve
as at 31 December 2018
Category
Tonnes
million
Grade
g/t
Contained gold
tonnes
Moz
VCR above 109 Level
Proved
0.00
7.85
0.02
0.00
Probable
0.01
6.21
0.04
0.00
Total
0.01
6.76
0.06
0.00
VCR 109 to 120 Level
Proved
0.27
7.47
1.99
0.06
Probable
0.51
8.07
4.12
0.13
Total
0.78
7.87
6.11
0.20
VCR below 120 Level
Proved
0.57
10.09
5.73
0.18
Probable
5.85
12.09
70.67
2.27
Total
6.41
11.91
76.39
2.46
VCR LOM extension project
Proved
–
–
–
–
Probable
1.69
9.69
16.41
0.53
Total
1.69
9.69
16.41
0.53
VCR WUDLs
Proved
–
–
–
–
Probable
6.10
10.46
63.81
2.05
Total
6.10
10.46
63.81
2.05
TauTona CLR Eastern block
Proved
0.58
5.45
3.17
0.10
Probable
1.23
9.09
11.21
0.36
Total
1.81
7.93
14.38
0.46
CLR LOM extension project
Proved
0.02
8.96
0.22
0.01
Probable
19.64
9.41
184.85
5.94
Total
19.66
9.41
185.07
5.95
Mponeng
Total
36.47
9.93
362.24
11.65
Estimation
The mine design process delineates the mining areas and supporting development for each mining level and section, usually
by extrapolating the existing mining design using the latest geological structure models and taking all relevant mine design
recommendations into consideration. The in situ Mineral Resource is scheduled monthly for the full LOM plan. The value estimates
for these schedules are derived from the Mineral Resource model.
Modifying factors are applied to the in situ Mineral Resource to arrive at an Ore Reserve estimate. These factors include a dilution
factor to accommodate the difference between the milling width and the stoping width, as well as the Mine Call Factor (MCF).
Ore Reserve modifying factors
As a deep underground mine, the Mineral Resource
at Mponeng is sensitive to a drop in gold price.
at Mponeng is sensitive to a drop in gold price.
Inclusive Mineral Resource sensitivity
33
SECTION 2 / SOUTH AFRICA
MPONENG CONTINUED
as at 31 December 2018
Gold
price
ZAR/kg
Cut-off
grade
g/t Au
Cut-off
value
cm.g/t Au
Stoping
width
cm
Dilution
%
MCF
%
MetRF
%
VCR above 109 Level
501,150
5.86
950
162.0
37.6
81.0
97.6
VCR 109 to 120 Level
501,150
6.03
950
157.5
38.0
81.0
97.6
VCR below 120 Level
501,150
7.27
950
130.7
41.1
81.0
97.9
VCR LOM extension project
501,150
7.08
950
134.2
47.7
83.1
97.6
VCR WUDLs
501,150
7.18
950
132.4
44.7
82.9
97.9
TauTona CLR Eastern Block
501,150
8.26
950
115.0
55.9
76.0
97.1
CLR LOM extension project
501,150
8.64
950
110.0
48.0
81.0
97.1
MCF is based on historic performance with consideration for current and future mining conditions.
Inferred Mineral Resource in business plan
as at 31 December 2018
Tonnes
million
Grade
g/t
Contained gold
tonnes
Moz
VCR WUDLs
3.21
11.03
35.45
1.14
CLR LOM extension project
0.20
9.97
2.01
0.06
Total
3.42
10.97
37.45
1.20
The Inferred Mineral Resource is used for optimisation purposes and forms part of the business plan but is not included in the Ore
Reserve. These portions of the Mineral Resource are located in the WUDLs area beyond current infrastructure on the VCR (LOM
extension project and Phase 5) and also make up part of the CLR Mineral Resource which is included in the CLR LOM extension
and Phase 6 project. This accounts for 9.4% of the business plan.
Ore Reserve below infrastructure
as at 31 December 2018
Category
Tonnes
million
Grade
g/t
Contained gold
tonnes
Moz
Mponeng
Proved
0.02
8.96
0.22
0.01
Probable
27.43
9.66
265.07
8.52
Total
27.46
9.66
265.29
8.53
The decrease of 4.2% in Ore Reserve is mainly due to the net effect of depletion, a revised estimation model for the VCR, the impact
of the removal of Savuka shaft pillars as well as the removal of certain high risk areas in the TauTona mining front.
Year-on-year changes in Ore Reserve
34
SECTION 2 / SOUTH AFRICA
35
SECTION 2 / SOUTH AFRICA
INTRODUCTION
Property description
Surface Operations comprise Vaal River Surface, MWS and West Wits Surface operations. The
operations produce gold by processing surface material such as low grade stockpiles and the
retreatment of TSFs.
Location
The Vaal River Surface operations are located to the north of the Vaal river, close to the town of
Orkney in the North West province. These operations extract gold from the low grade stockpile
material emanating as a by-product of the reef mining activities within the mines in the Vaal River
area. The MWS operations are located approximately 15km from the town of Klerksdorp near
Stilfontein within 20km of the Vaal River Surface operations. The MWS feed sources (TSFs) are
scattered over an area that stretches approximately 13.5km north-south and 14km east-west.
The West Wits Surface operations are located near the town of Carletonville, straddling the border
between the North West and Gauteng provinces.
History
Gold from surface material has been produced routinely since 2002. AngloGold Ashanti acquired
the MWS Mineral Resource and tailings retreatment operations in the Vaal River region in July 2012.
The MWS uranium and flotation plants were commissioned in 2014. Changes were made to the
configuration of the flotation and uranium processes after which the float plant was recommissioned
in July 2016 and the uranium plant in October 2016. These plants were reconfigured into an even
more efficient configuration during 2016. As part of the optimisation in 2017, the uranium and
fiotation plants were decommissioned.
Legal aspects and tenure
The MWS license to mine is covered by the environmental authorisation under the National
Environmental Management Act No. 107 of 1998. In terms of the current legislation, the Mineral and
Petroleum Resources Development Act No. 28 of 2002 (the MPRDA), a mining right is not required
to reclaim TSFs. MWS can prove ownership and tenure of the operations. There was pending
legislation that, once passed, would require a mining right to be obtained in order to mine TSFs.
This Amendment Bill has subsequently been withdrawn by the Minister of Mineral Resources until
further notice.
Following the Sale of the Vaal River underground operations, the Vaal River mining rights were
transferred to Harmony, who acquired the Moab Khotsong Operations and Village Main Reef, who
acquired the Kopanang Operations. In terms of the Vaal River Surface operations, the appropriate
authorisation is currently in the process of being applied for.
The current mining rights for the South African operations cover multiple horizons, i.e. both
underground and surface for West Wits region. The TSFs falling outside the mining right are
accommodated in the approved EMP and financial provision for rehabilitation for the West Wits
Mining Rights, as well as under historic surface rights permits for West Wits, which are still valid.
A S102 application was submitted in March 2017 to consolidate West Wits Surface into
GP30/5/1/2/2(01)MR.
Mining method
Low grade stockpiles
Bulldozers are used to create safe loading faces. The material is then loaded from the face onto
rail hoppers or trucks by means of front-end loaders and transported to the relevant gold plants
for processing.
TSFs
The tailings are reclaimed using a number of hydraulic (high-pressure water) monitoring guns to
deliver water at pressure, typically 27-30 bar, to the face. The tailings material is reclaimed by
blasting the TSF face with the high-pressure water, resulting in the slurry gravitating towards pump
stations. These monitoring guns can be positioned to selectively reclaim required areas from the
TSFs. Bench heights are constrained by the force delivered from the monitoring gun nozzle and
safety constraints. With sufficient pressure, face lengths of up to 25m can be reclaimed.
The pump stations are located at the lowest point of the dams to ensure that the slurry from the
dams will gravitate towards the pump station from where it will be pumped to the processing plants.
SURFACE OPERATIONS
36
SECTION 2 / SOUTH AFRICA
Operational infrastructure
Low grade stockpiles in the Vaal River area are processed through the Kopanang Gold Plant which
is a dedicated surface sources metallurgical plant while all AGA owned tailings material in the Vaal
River and MWS areas is processed through the three metallurgical streams at the MWS metallurgical
operations. At West Wits, material from both low grade stockpiles and TSF is processed through the
Savuka gold plant. Low grade stockpile material is processed through the Mponeng gold plant to fill
the processing gap and to ensure adequate supply of backfill material to Mponeng shaft. Adequate
deposition capacity for the Surface Operations exists in all areas.
Operational infrastructure road, rail, offices, security services, water and power supply is adequate,
and is shared with the AngloGold Ashanti operations in the relevant areas.
Mineral processing
The mineral process is dependent on the source material: tailings material is pumped directly to a
conventional carbon-in-leach (CIL) plant while hard rock material will go through comminution first,
and then be processed through leach followed by CIP.
MWS comprises three separate streams namely Stream 1, Stream 2 and Stream 3. Hydraulically-
reclaimed material from several TSF sites is pumped via the 3 pump stations to the MWS plant
streams for gold extraction.
The West Wits Surface Operations process low grade stockpile material sourced from the mining of
the CLR and the VCR that are mined by the West Wits mines in the Carletonville/Fochville area, as
well as hydraulically-reclaimed material from the Old North TSF.
Within the Vaal River area, the Kopanang Gold plant is a dedicated surface operation plant. In the
West Wits area, the Savuka gold plant is dedicated to process surface sources material while low
grade stockpile material is processed through Mponeng gold plant to fill the processing gap.
Risks
There are no known unmanaged risks that may affect reclamation activities.
The increased recovery over MWS LOM is associated with the project to introduce Aachen
Reactors in the 3 streams and is still being evaluated.
Map showing MWS and Vaal River Surface infrastructure and properties
Mine infrastructure
Plant
Stockpiles
TSF
Tailings pipeline
AGA property
Chemwes
Settlements
Towns
Villages
Roads
Main
River
River
MWS centroid co-ordinates
26°48’00”E, 26°50’05”S
2.5
0
2.5
5
7.5km
37
SECTION 2 / SOUTH AFRICA
SURFACE OPERATIONS CONTINUED
Map showing West Wits Surface and Mponeng Mine infrastructure and licences
Competent Persons
Responsibility
Competent Person
Professional
organisation
Membership
number
Relevant
experience
Qualification
Mineral Resource
Mmatseleng Maipushi
SACNASP
114 390
8 years
BSc Hons (Geology)
Ore Reserve
Mariaan Gagiano
SAIMM
705 920
34 years
Government Certificate of
Competency in Assaying (GCC)
GEOLOGY
The material contained in the TSFs and low grade stockpiles originates from the historic ore-bearing reefs mined by the West Wits,
Vaal River, Buffelsfontein, Hartebeestfontein and Stilfontein gold mines.
Low grade stockpiles
The low grade stockpiles consist of waste rock mined from underground workings, hoisted, transported and deposited via conveyor
belts. The gold contained within these dumps was sourced from three areas namely:
•
Minor reef intersected while accessing the primary reef
•
Gold-bearing reef that was contained within small fault blocks that were exposed by off-reef development
•
Cross-tramming of gold-bearing reef material to the waste tips
Mponeng
plant centroid co-ordinates
27°26’06”E, 26°26’11”S
Licences
Mining
Surface property
Mine infrastructure
Mine area
Plant
Stockpiles
TSF
Tailings pipeline
Underground workings
Settlements
Towns
Villages
Roads
Main
Secondary
1
0
1
2km
38
SECTION 2 / SOUTH AFRICA
Tailings storage facilities
The TSFs consist of tailings material which originated from the processing of the underground ore from the various operations
in the Vaal River area (Vaal Reef Surface), the various operations in West Wits area (West Wits Surface) and Buffelsfontein,
Hartebeestfontein and Stilfontein gold mines (MWS). These gold mines are deep level gold mines, which predominantly extract the
tabular, conglomeratic Vaal Reef (VR), CLR and VCR. The VR has been predominantly mined for gold in the past although the reef
also contains uranium oxide. The same is true but, to a lesser extent, with the CLR and VCR. The material contained in the TSFs is
fine in nature. The footprints of the MWS TSFs and Vaal River Surface operations TSFs cover an area of approximately 1,100ha.
South East TSF grade model section view along the west to east direction
Gold Grade (g/t)
0
100
200
300
700
600
500
400
1:7,500
Gold Grade (g/t)
0 – 0.164
0.164 – 0.185
0.185 – 0.230
0.230 – 0.241
0.241 – 0.299
0.299 – 0.345
0.345 – 0.402
>= 0.402
PROJECTS
MWS plant deposition takes place on the Kareerand TSF. The existing Kareerand TSF was commissioned in 2011 with a design life
of 14 years to 2025 at a tailings throughput rate of 1.9 million tonnes per month (Mtpm). Since commissioning, MWS has ramped
up production and has targeted a total tailings throughput rate of 2.5 Mtpm until 2042.The increased deposition on the existing
facility means that the TSF will reach its limiting rate of rise sooner than 2025, with consequent loss of storage capacity. A PFS
has been concluded to establish the best option for expanding the capacity, and confirming the technical and financial viability of
the project. Work on applying for the permits required to construct the TSF extension has begun and the application process will
commence in 2019.
39
SECTION 2 / SOUTH AFRICA
SURFACE OPERATIONS CONTINUED
MINERAL RESOURCE
Details of average drill hole spacing and type in relation to Mineral Resource classification
Category
Spacing m (-x-)
Type of drilling
Comments
Diamond
RC
Blasthole
Channel
Other
Vaal River Surface
Measured
50 x 50
–
–
–
–
√
Auger drilling
Indicated
100 x 100 to 150 x 150
–
–
–
–
√
Auger drilling
Inferred
–
–
–
–
–
–
–
Grade/ore control
50 x 50 to 100 x 100
–
–
–
–
√
Auger drilling
Mine Waste Solutions
Measured
100 x 100 to 320 x 250
–
–
–
–
√
Auger drilling
Indicated
100 x 100 to 300 x 375
–
–
–
–
√
Auger drilling
Inferred
–
–
–
–
–
–
–
Grade/ore control
50 x 50 to 100 x 100
–
–
–
–
√
Auger drilling
West Wits Surface
Measured
–
–
–
–
–
–
–
Indicated
150 x 150
–
–
–
–
√
Auger drilling
Inferred
–
–
–
–
–
–
–
Grade/ore control
150 x 150
–
–
–
–
√
Auger drilling
In the case of TSFs, additional sampling information is available in the form of residue sampling data collected during deposition on
the TSFs.
40
SECTION 2 / SOUTH AFRICA
Inclusive Mineral Resource
as at 31 December 2018
Category
Tonnes
million
Grade
g/t
Contained gold
tonnes
Moz
Vaal River Surface
TSFs
Measured
–
–
–
–
Indicated
323.63
0.25
82.42
2.65
Inferred
–
–
–
–
Total
323.63
0.25
82.42
2.65
Low grade stockpiles
Measured
–
–
–
–
Indicated
–
–
–
–
Inferred
10.09
0.51
5.13
0.16
Total
10.09
0.51
5.13
0.16
Mine Waste Solutions
TSFs
Measured
105.96
0.21
22.76
0.73
Indicated
172.57
0.26
44.94
1.44
Inferred
–
–
–
–
Total
278.53
0.24
67.71
2.18
West Wits Surface
TSFs
Measured
–
–
–
–
Indicated
55.10
0.30
16.31
0.52
Inferred
0.86
0.30
0.26
0.01
Total
55.96
0.30
16.57
0.53
Low grade stockpiles
Measured
–
–
–
–
Indicated
5.56
0.50
2.80
0.09
Inferred
–
–
–
–
Total
5.56
0.50
2.80
0.09
Surface Operations
Total
673.77
0.26
174.62
5.61
Inclusive Mineral Resource by-product: uranium
as at 31 December 2018
Category
Tonnes
million
Grade
kg/t
Contained uranium
tonnes pounds million
Vaal River Surface
Measured
–
–
–
–
Indicated
323.63
0.08
25,430
56.06
Inferred
–
–
–
–
Total
323.63
0.08
25,430
56.06
Mine Waste Solutions
Measured
105.96
0.07
7,228
15.94
Indicated
172.57
0.08
13,886
30.61
Inferred
–
–
–
–
Total
278.53
0.08
21,115
46.55
Surface Operations
Total
602.16
0.08
46,544
102.61
41
SECTION 2 / SOUTH AFRICA
SURFACE OPERATIONS CONTINUED
Estimation
TSFs
Prior to 2011 for the Vaal River operations, the grade estimations for the TSFs were based on the residue grades obtained from the
different process plants, as well as various ad hoc sampling projects in selected areas. Most of the TSFs in Vaal River and MWS
have since been re-sampled by means of an extensive drilling exercise which commenced in 2011. The remainder TSFs will be re-
sampled once the TSFs become dormant. A stringent QA/QC process was applied to the sampling and assay processes to ensure
a high level of confidence in the results. The auger drilling typically took place on a 150 x 150m grid (Mineral Resource model) as
well as a minimum of a 50 x 50m grid (grade control model). The vertical sampling interval of 1.5m was implemented and where
possible all drill holes were drilled into the underlying strata to allow the estimation of the base of the TSF. The estimation technique
used is 3D ordinary kriging. The variograms used for the grade estimation consist of both horizontal and downhole variograms. The
methodology used for the construction of the grade model constitutes well defined 3D wireframes which are constructed using the
drill holes and the results from monthly surveys on currently reclaimed TSFs and aerial surveys carried out on an annual basis for
TSFs which are planned to be reclaimed. These models are regularly updated during the grade control process.
In the West Wits Surface operations, all the grade estimations for the TSFs were based on the residue grades obtained from
the different process plants as well as various ad hoc sampling projects in selected areas. For one of these areas, the Old North
Complex, a drilling programme with the standard QA/QC programme was implemented in 2015. The drilling was completed in 2018
and the 3D estimate will be finalised in 2019.
Low grade stockpiles
In the West Wits and Vaal River operations, the grade estimation is based on grades obtained from reclaimed tonnages from the
different stockpiles, grades obtained from rock deposited on these facilities and grades from various other sampling projects carried
out on some of the stockpiles. These sampling exercises involved a pit being dug on a pre-determined grid on the low grade
stockpiles from which samples were taken. These samples were then split into different size fractions and assayed to determine the
gold distribution for the different size fractions. The profiles of the stockpiles are also updated by means of aerial surveys carried out
on an annual basis. Sampling is done by means of mechanical stop belt samplers on the feed belts at the metallurgical plants.
Changes in the Mineral Resource are mainly due to Mispah 1, Kopanang Paydam TSFs and Moab Khotsong low grade stockpile
being moved out of the Mineral Resource following the Harmony sale, the acquisition of new low grade stockpiles into Inferred
Mineral Resource and normal depletion of the Mineral Resource.
Year-on-year changes in Mineral Resource
42
SECTION 2 / SOUTH AFRICA
ORE RESERVE
Ore Reserve
as at 31 December 2018
Category
Tonnes
million
Grade
g/t
Contained gold
tonnes
Moz
Vaal River Surface
TSFs
Proved
–
–
–
–
Probable
324.23
0.25
82.42
2.65
Total
324.23
0.25
82.42
2.65
Mine Waste Solutions
TSFs
Proved
106.23
0.21
22.76
0.73
Probable
172.79
0.26
44.94
1.44
Total
279.02
0.24
67.71
2.18
West Wits Surface
TSFs
Proved
–
–
–
–
Probable
27.60
0.29
7.97
0.26
Total
27.60
0.29
7.97
0.26
Low grade stockpiles
Proved
–
–
–
–
Probable
4.37
0.49
2.14
0.07
Total
4.37
0.49
2.14
0.07
Surface Operations
Total
635.23
0.25
160.23
5.15
Surface Operations is not sensitive to changes in
gold price.
gold price.
Inclusive Mineral Resource sensitivity
43
SECTION 2 / SOUTH AFRICA
SURFACE OPERATIONS CONTINUED
Estimation
TSFs
Mine design models delineate the areas to be reclaimed over the life of the operations, taking all relevant mine design
recommendations into consideration. The in situ Mineral Resource is scheduled for the full LOM plan. The value estimates for these
schedules are derived from the Mineral Resource block models where they exist. The benefit of the reclamation of the surface
sources and subsequent rehabilitation of the relevant areas is included in the evaluation of the feasibility of the project.
Low grade stockpiles
Planned reclamation from the low grade stockpiles is scheduled out to ensure an average blend. The in situ Mineral Resource is
scheduled for the full LOM plan. The value estimates for these schedules are derived from the Mineral Resource estimate with an
18 month reconciliation factor applied to the Mineral Resource.
Ore Reserve modifying factors
as at 31 December 2018
Gold
price
ZAR/kg
Cut-off
grade
g/t Au
RMF
% (based
on tonnes)
RMF
% (based
on g/t)
MCF
%
MetRF
%
Vaal River Surface
TSFs
501,150
0.23
100.0
100.0
100.0
52.8
Mine Waste Solutions
TSFs
501,150
0.23
100.0
100.0
100.0
52.8
West Wits Surface
TSFs
501,150
0.29
100.0
100.0
100.0
45.0
Low grade stockpile
501,150
0.28
100.0
85.0
100.0
88.0
10% margin applied for cut-off grade calculations apart from Vaal River Surface low grade stockpiles which uses a 5% margin.
Minor dilution of the TSF tonnes occurs when reclamation of the floor area of the TSF is done. During reclamation it is also possible
that small quantities of basement material is included with the TSF floor material. A small dilution factor has been included to
account for them both. The metallurgical recovery factor (MetRF) for TSF material ranges between 42% and 60% depending on the
metallurgical plant and for low grade stockpile material processed ranges between 87% and 90%.
For the low grade stockpiles a Mineral Resource factor is applied which is based on an 18 month rolling average of the actual
evaluation factor.
Inferred Mineral Resource in business plan
as at 31 December 2018
Tonnes
million
Grade
g/t
Contained gold
tonnes
Moz
Vaal River Surface
Low grade stockpile
9.45
0.50
4.71
0.15
Total
9.45
0.50
4.71
0.15
44
SECTION 2 / SOUTH AFRICA
In addition to normal depletion’s in all areas during 2018 Ore Reserve, the Moab Khotsong low grade stockpile and Kopanang TSF
were included in the sale to Harmony and thus excluded from the Ore Reserve estimate this year.
Year-on-year changes in Ore Reserve
45
SECTION 2 / SOUTH AFRICA
CONTINENTAL AFRICA
LEGEND
1
Guinea Siguiri (85%)
2
Mali Morila (40%)/Sadiola (41%)
3
Ghana Iduapriem/Obuasi
4
DRC Kibali (45%)
5
Tanzania Geita
2,000km
Project
Operation
0
Tanzania – Geita
CONTENTS
Regional overview
47
DRC
50
Ghana
62
Guinea
86
Mali
102
Tanzania
120
46
SECTION 3 / CONTINENTAL AFRICA
REGIONAL OVERVIEW
Key statistics
Units
2018
2017
2016
Operational performance
Tonnes treated/milled
Mt
27.3
28.0
27.6
Recovered grade
oz/t
0.050
0.047
0.043
g/t
1.72
1.61
1.49
Gold production (attributable)
000oz
1,512
1,453
1,321
Total cash costs
$/oz
773
720
717
Total production costs
$/oz
1,028
1,012
1,005
All-in sustaining costs
(1)
$/oz
904
953
904
Capital expenditure (attributable)
$m
313
409
291
(1)
Excludes stockpile write-offs
As at December 2018, the total attributable Mineral Resource (inclusive of the Ore Reserve) for the Continental
Africa region was 64.1Moz (2017: 64.1Moz) and the attributable Ore Reserve 16.3Moz (2017: 16.9Moz).
Africa region was 64.1Moz (2017: 64.1Moz) and the attributable Ore Reserve 16.3Moz (2017: 16.9Moz).
This is equivalent to 35% and 37% of the group’s Mineral Resource and Ore Reserve respectively. Combined production from these
operations totalled 1.512Moz of gold in 2018, or 45% of group production.
AngloGold Ashanti has seven mining operations within the Continental Africa region:
•
Kibali in the Democratic Republic of the Congo (DRC), a joint venture (JV) with Barrick Gold Corporation (Barrick) and Société
Minière de kilo-Moto (SOKIMO), the state-owned gold mining company
•
Iduapriem in Ghana
•
Obuasi in Ghana
•
Siguiri in Guinea
•
Morila in Mali, a JV with Barrick and the state of Mali
•
Sadiola in Mali, a JV with IAMGOLD and the state of Mali
•
Geita in Tanzania
Mining is from both open pit and underground, with Obuasi being an underground mine, Iduapriem, Siguiri and Sadiola being open
pit mines and Kibali and Geita being a combination of open pit and underground mines. Morila is primarily a tailings retreatment
operation.
47
SECTION 3 / CONTINENTAL AFRICA
REGIONAL OVERVIEW CONTINUED
Inclusive Mineral Resource
as at 31 December 2018
Category
Tonnes
million
Grade
g/t
Contained gold
tonnes
Moz
Continental Africa
Measured
42.17
2.04
85.94
2.76
Indicated
469.94
2.57
1,209.71
38.89
Inferred
202.51
3.43
695.30
22.35
Total
714.62
2.79
1,990.95
64.01
Exclusive Mineral Resource
as at 31 December 2018
Category
Tonnes
million
Grade
g/t
Contained gold
tonnes
Moz
Continental Africa
Measured
5.05
4.85
24.49
0.79
Indicated
292.05
2.56
747.70
24.04
Inferred
199.75
3.47
693.42
22.29
Total
496.85
2.95
1,465.62
47.12
Ore Reserve
as at 31 December 2018
Category
Tonnes
million
Grade
g/t
Contained gold
tonnes
Moz
Continental Africa
Proved
35.92
1.57
56.31
1.81
Probable
170.89
2.64
451.70
14.52
Total
206.81
2.46
508.01
16.33
48
SECTION 3 / CONTINENTAL AFRICA
Guinea – Siguiri
49
SECTION 3 / CONTINENTAL AFRICA
DEMOCRATIC REPUBLIC OF THE CONGO
AngloGold Ashanti owns 45% of
Kibali in the DRC.
The operation is a JV between
three separate entities:
• AngloGold Ashanti
• Barrick, following its merger
with Randgold Resources
Limited
• Société Minière de kilo-Moto
(SOKIMO), the state-owned gold
mining company
The consolidated lease is made
up of 10 mining concessions.
DRC – Kibali
50
SECTION 3 / CONTINENTAL AFRICA
Inclusive Mineral Resource
as at 31 December 2018
Category
Tonnes
million
Grade
g/t
Contained gold
tonnes
Moz
Democratic Republic of the Congo
Measured
9.17
4.60
42.16
1.36
Indicated
44.71
3.05
136.37
4.38
Inferred
23.77
2.50
59.40
1.91
Total
77.65
3.06
237.93
7.65
Exclusive Mineral Resource
as at 31 December 2018
Category
Tonnes
million
Grade
g/t
Contained gold
tonnes
Moz
Democratic Republic of the Congo
Measured
1.42
2.68
3.81
0.12
Indicated
22.68
2.43
55.11
1.77
Inferred
23.77
2.50
59.40
1.91
Total
47.87
2.47
118.32
3.80
Ore Reserve
as at 31 December 2018
Category
Tonnes
million
Grade
g/t
Contained gold
tonnes
Moz
Democratic Republic of the Congo
Proved
9.14
4.15
37.87
1.22
Probable
19.08
4.12
78.70
2.53
Total
28.22
4.13
116.57
3.75
LEGEND
1
Kibali (45%)
Operation
300km
0
51
SECTION 3 / CONTINENTAL AFRICA
KIBALI
INTRODUCTION
Property description
Operations presently focus on open pit and underground mining. Development of the underground
mine commenced in 2013 and production ramped up to 3.5Mt in 2018. Initial production was via
a twin decline from surface. From 2018 the majority of ore is hoisted up the shaft. The decline to
surface is used to haul some of the shallower zones and to supplement shaft haulage.
Location
Kibali is located in the north-eastern part of the DRC near the international borders with Uganda and
South Sudan. The mine is located adjacent to the village of Doko, which is located to the west of
the lease area. Kibali is approximately 210km by road from Arua and immediately north of the district
capital of Watsa. The operations area falls within the administrative territory of Watsa in Haut-Uélé
province.
History
On 15 October 2009, AngloGold Ashanti acquired a 50% indirect interest in Moto Goldmines Limited
through a JV with Randgold, with Moto holding a 70% stake in Kibali and the balance (30%) being
held by the DRC parastatal, SOKIMO. On 21 December 2009, Randgold and AngloGold Ashanti
increased their JV interest in Kibali to 90%, while SOKIMO retained a 10% holding. On 2 January
2019, Randgold Resources Limited merged with Barrick Gold Corporation and the JV is now with
the combined company, trading as Barrick Gold Corporation (Barrick).
First gold was poured in September 2013 from the open pit operations. Development of the
underground mine commenced in 2013. The first underground development ore was mined in 2013
and stoping commenced in 2015. Underground production has since ramped up to 1.8Mt in 2017
and 3.5Mt in 2018. Initial production was truck hauled by a twin decline to surface. In 2017 the
haulage shaft (740m deep) and materials handling system were commissioned.
Legal aspects and tenure
The total Ore Reserve is covered by exploitation permits (11447, 11467, 11468, 11469, 11470,
11471, 11472, 5052, 5073 and 5088) totalling 1,836km2. Kibali gold mine has been granted the ten
exploitation permits under the DRC mining code, seven of which are valid until 2029 and three are
valid until 2030.
Mining method
The mine comprises both open pit and underground mining. The open pit Ore Reserve shell
optimisations are conducted on the Mineral Resource models. Detailed mine designs are then
completed for open pit mining. This incorporates the mining layout, operating factors, stripping ratio
and relevant cut-off grades and modifying factors required for the reporting of Ore Reserve.
For the underground operation, longitudinal and transverse longitudinal stoping methods with paste
backfill are the current underground mining methods.
Operational infrastructure
The mine site is located within 160km of the border with Uganda and all transport links take place
through Uganda to Kenya or Tanzania. Surface infrastructure associated with the overall Kibali
operation includes a processing plant, tailings storage facility, camp, hydro and thermal power
stations, airstrip, workshops and offices.
All necessary government agreements and approvals required for the mine are in place.
Mineral processing
The current processing plant can treat both oxide and fresh sulphide material and is configured for
otation and ultra-fine grind of the flotation concentrate, a treatment that is required for the sulphide
ore type before leaching.
Risks
There are no known material risks that will impact on the Mineral Resource and Ore Reserve.
Competent Persons
Responsibility
Competent Person
Professional
organisation
Membership
number
Relevant
experience
Qualification
Mineral Resource and
Ore Reserve
Simon Bottoms*
Geological Society
of London
(FGS CGeol)
1 023 769
9 years
MGeol
* Employed by Barrick as SVP, Africa and Middle East Mineral Resource Manager, 3rd Floor, Unity Chambers, 28 Halkett Street, St. Helier, Jersey,
Channel Islands
52
SECTION 3 / CONTINENTAL AFRICA
Map showing Kibali Mine infrastructure and licences with the total mining lease area insert shown
in the top right-hand corner
in the top right-hand corner
Licences
Mining
Mine Infrastructure
Pits
Plant
Stockpiles
TSF
Waste dumps
Underground workings
Settlements
Towns
Villages
Roads
Main
Secondary
Airfield
Insert
Total mining lease area
Map zoomed in area
0
1
2
3km
Plant centroid co-ordinates
29°35’31”E, 3°6’50”N
0
10
20km
Total mining lease area
53
SECTION 3 / CONTINENTAL AFRICA
KIBALI CONTINUED
54
SECTION 3 / CONTINENTAL AFRICA
GEOLOGY
Deposit type
Deposits of the Kibali district are located in the Archean Moto Greenstone Belt bounded to the north by the West Nile Gneiss and
to the south by plutonic rocks of the Watsa district. The belt comprises three lithostratigraphically distinct blocks. Psammopelitic
schists, amphibolite, banded iron formation, and gneissic granitoid sills metamorphosed under upper greenschist to low-mid-
amphibolite facies conditions form the eastern part of the belt. Relative weakly foliated basalts, cherts, siliciclastic rocks, dacitic
volcanoclastic rocks, and carbonaceous argillite metamorphosed under mid to upper greenschist facies conditions comprise
the central and western-most parts of the belt. Granitoid plutons as old as ca. 2,640Ma intrude these rocks. A thick package of
immature sandstone, gritstone, conglomerate, and probably acid tuffs forms much of the western part of the belt, including the host
rocks to Karagba, Chauffeur and Durba (KCD), the largest deposit discovered to date within the belt. Radiometric dating indicates
these siliclastic rocks were deposited during a belt-wide basin extension event between ca. 2,629Ma and 2,626Ma with much of
the detritus derived from adjacent older parts of the belt.
schists, amphibolite, banded iron formation, and gneissic granitoid sills metamorphosed under upper greenschist to low-mid-
amphibolite facies conditions form the eastern part of the belt. Relative weakly foliated basalts, cherts, siliciclastic rocks, dacitic
volcanoclastic rocks, and carbonaceous argillite metamorphosed under mid to upper greenschist facies conditions comprise
the central and western-most parts of the belt. Granitoid plutons as old as ca. 2,640Ma intrude these rocks. A thick package of
immature sandstone, gritstone, conglomerate, and probably acid tuffs forms much of the western part of the belt, including the host
rocks to Karagba, Chauffeur and Durba (KCD), the largest deposit discovered to date within the belt. Radiometric dating indicates
these siliclastic rocks were deposited during a belt-wide basin extension event between ca. 2,629Ma and 2,626Ma with much of
the detritus derived from adjacent older parts of the belt.
Boundaries between these lithostratigraphic blocks represent important exploration targets.
The main Kibali deposit consists of the combination of the KCD deposit. Currently only the KCD deposit hosts an underground Ore
Reserve and this constitutes 84% of the total KCD Ore Reserve.
Reserve and this constitutes 84% of the total KCD Ore Reserve.
Mineralisation style
Gold deposits of the Kibali district are classified as Archean orogenic gold deposits. At Kibali, the gold deposits are largely hosted
in siliciclastic rocks, banded iron formations and chert that were metamorphosed under greenschist facies conditions. Ore-forming
H
in siliciclastic rocks, banded iron formations and chert that were metamorphosed under greenschist facies conditions. Ore-forming
H
2
O-CO
2
-rich fluids migrated along a linked network of gently northeast-dipping shears and northeast to north-northeast plunging
fold axes that is commonly referred to as the KZ Trend. The richly mineralised KZ Trend appears to have initiated as an extensional
fault system along the boundary between the relatively young basin in the western part of the belt and older rocks to the east.
Mineralisation occurred during the later stages of subsequent regional contractional deformation, which resulted in inversion of the
basin and the development of reverse faults and folds. Ongoing deformation during hydrothermal activity resulted in development
of lodes in a variety of related structural settings within the KZ Trend. The source(s) of metal and fluids, which formed the deposits
remain unknown, but metamorphic devolatilisation reactions within the supracrustal rocks of the Moto Greenstone Belt and/or
deeper fluid and metal sources may have contributed.
fault system along the boundary between the relatively young basin in the western part of the belt and older rocks to the east.
Mineralisation occurred during the later stages of subsequent regional contractional deformation, which resulted in inversion of the
basin and the development of reverse faults and folds. Ongoing deformation during hydrothermal activity resulted in development
of lodes in a variety of related structural settings within the KZ Trend. The source(s) of metal and fluids, which formed the deposits
remain unknown, but metamorphic devolatilisation reactions within the supracrustal rocks of the Moto Greenstone Belt and/or
deeper fluid and metal sources may have contributed.
Mineralisation characteristics
Gold deposits of the Kibali district are associated with halos of quartz, ankerite and sericite (ACSA-A alteration) that extend for 10s
to 100s of metres into the adjacent rocks. This widespread ACSA-A alteration assemblage is superimposed on older greenschist
facies metamorphic assemblages. Locally in the vicinity of the main mineralised zones ACSA-A alteration is overprinted by ankerite-
siderite, pyrite alteration (ACSA-B) that hosts the ore. Gold is directly associated with the ACSA-B alteration assemblage. In smaller
peripheral deposits a late chlorite, carbonate, pyrite assemblage is associated with the ore rather than the ACSA-B assemblage,
implying a district-wide zonation of mineral assemblages along and across the mineralised KZ Trend. Zones of auriferous ACSA-B
alteration are commonly developed along the margins of banded iron formation, or contacts between chert, carbonaceous phyllite,
and banded iron formation. Mineralised rocks in the Kibali district typically lack significant infill quartz-rich veins, unlike many other
orogenic gold deposits. Gold is instead associated with pyrite in zones of alteration that replaced the earlier mineralogy of the host
rocks. Local remobilisation and upgrading of ACSA-B related ore occurred adjacent to the margins of some post-ore crosscutting
chlorite, carbonate, pyrite, magnetite-altered diorite dykes.
to 100s of metres into the adjacent rocks. This widespread ACSA-A alteration assemblage is superimposed on older greenschist
facies metamorphic assemblages. Locally in the vicinity of the main mineralised zones ACSA-A alteration is overprinted by ankerite-
siderite, pyrite alteration (ACSA-B) that hosts the ore. Gold is directly associated with the ACSA-B alteration assemblage. In smaller
peripheral deposits a late chlorite, carbonate, pyrite assemblage is associated with the ore rather than the ACSA-B assemblage,
implying a district-wide zonation of mineral assemblages along and across the mineralised KZ Trend. Zones of auriferous ACSA-B
alteration are commonly developed along the margins of banded iron formation, or contacts between chert, carbonaceous phyllite,
and banded iron formation. Mineralised rocks in the Kibali district typically lack significant infill quartz-rich veins, unlike many other
orogenic gold deposits. Gold is instead associated with pyrite in zones of alteration that replaced the earlier mineralogy of the host
rocks. Local remobilisation and upgrading of ACSA-B related ore occurred adjacent to the margins of some post-ore crosscutting
chlorite, carbonate, pyrite, magnetite-altered diorite dykes.
The location of the individual lodes within the KCD deposit are intimately controlled by the position, shape, and orientation of a
series of gently northeast-plunging tight to isoclinal folds. The ACSA-A alteration developed during the formation of these folds,
and the sericite foliation which is an integral part of the ACSA-A assemblage formed parallel to their axial planes. Zones of later
auriferous ACSA-B alteration developed along the axes, limbs, and more rarely the axial planes of these folds, locally wrapping
around the hinges of the folds to form elongate northeast-plunging concave-shaped rods. ACSA-B alteration is also commonly
focused along the margins of more extensive banded iron formations, indicating a stratigraphic as well as structural control on the
distribution of ore, both within KCD, and other parts of the wider KZ Trend. Shear zones that were active during folding are a third
key structural control on the location of ore within KCD and the wider KZ Trend. At KCD a folded carbonaceous shear in the core of
the deposit juxtaposes stratigraphically distinct blocks. The 3,000 lodes above this shear are hosted by locally ferruginous cherts,
carbonaceous argillites, and minor greywacke, whereas the 5,000 and 9,000 lodes below are hosted by siliciclastic rocks and
banded iron formation. Fold shapes and wavelength differ between the two blocks reflecting their different rheologies during folding,
and this is reflected in the scale, shape, and continuity of lodes in each block. At Pakaka and Kalimva chlorite, carbonate, pyrrhotite,
pyrite-altered shear zones rather than folds are the principal controls on gold distribution.
series of gently northeast-plunging tight to isoclinal folds. The ACSA-A alteration developed during the formation of these folds,
and the sericite foliation which is an integral part of the ACSA-A assemblage formed parallel to their axial planes. Zones of later
auriferous ACSA-B alteration developed along the axes, limbs, and more rarely the axial planes of these folds, locally wrapping
around the hinges of the folds to form elongate northeast-plunging concave-shaped rods. ACSA-B alteration is also commonly
focused along the margins of more extensive banded iron formations, indicating a stratigraphic as well as structural control on the
distribution of ore, both within KCD, and other parts of the wider KZ Trend. Shear zones that were active during folding are a third
key structural control on the location of ore within KCD and the wider KZ Trend. At KCD a folded carbonaceous shear in the core of
the deposit juxtaposes stratigraphically distinct blocks. The 3,000 lodes above this shear are hosted by locally ferruginous cherts,
carbonaceous argillites, and minor greywacke, whereas the 5,000 and 9,000 lodes below are hosted by siliciclastic rocks and
banded iron formation. Fold shapes and wavelength differ between the two blocks reflecting their different rheologies during folding,
and this is reflected in the scale, shape, and continuity of lodes in each block. At Pakaka and Kalimva chlorite, carbonate, pyrrhotite,
pyrite-altered shear zones rather than folds are the principal controls on gold distribution.
55
SECTION 3 / CONTINENTAL AFRICA
KIBALI CONTINUED
NW-SE Geological cross-section through the KCD orebody, elevation in metres relative to average mean sea level
0
50km
Younging direction
Inferred major fault
Fold axial plane
Chert
BIF
Carbonaceous phyllite
ACSA-A alteration
Disseminated magnetite cubes and/or relic BiF
Disseminated magnetite cubes and/or
relic BiF in ACSA-B (altered BIF rocks)
relic BiF in ACSA-B (altered BIF rocks)
ACSA-B alteration
Late carbonaceous shear
Mafic dyke
Mineralisation
KCD current pit outline
56
SECTION 3 / CONTINENTAL AFRICA
EXPLORATION
In 2018, exploration focused on the down plunge and up plunge extensions of the KCD 3000, 5000 and 9000 lodes. The 3000 lode
was drilled from surface to upgrade and convert Inferred Mineral Resource to Indicated Mineral Resource and allow for conversion
to open pit Ore Reserve, while drilling was conducted from underground to test the down plunge extents. The down plunge extent
of the 5000 lode above the haulage level was targeted to test for continuity of the 5101 and 5102 lodes a further 250m down
plunge from the known Mineral Resource. The drilling on the 3000 and 5000 lodes was conducted from a dedicated underground
exploration drill drive on the 290 Level. On the 9000 lode, the gap between the Sessenge Pit and 9000 lode underground was drill
tested from surface on a 100 x 100m spacing to determine continuity and grade distribution.
Alongside this, 2018 regional exploration focused on new discoveries, near mine opportunities, and Mineral Resource additions.
The most notable result was the definition of an Inferred Mineral Resource at Kalimva and Ikamva, which replaced the 2018 annual
depletion of Kibali Mineral Resource. In addition, first pass Reverse Circulation (RC) drilling was performed at Oere, successfully
identifying a 2km shear zone.
The 2019 regional exploration will continue to focus on the identification of new opportunities and the testing of gaps between
known Mineral Resource such as the Gorumbwa-Sessenge Gap. Further Mineral Resource extension exploration is scheduled
to target the down plunge extensions of the KCD 5000 lode focussing above the bottom level of the shaft, with drilling from a
dedicated underground exploration drill drive. In addition, a PFS will be completed with the target of upgrading of Kalimva and
Ikamva Inferred Mineral Resource to an Indicated Mineral Resource, and defining appropriate modifying factors such that they can
be incorporated into an Ore Reserve.
PROJECTS
Underground ore production more than doubled from 2017, with 3,465kt mined during the first year of full vertical shaft operation.
During 2019 the evaluation of a new Waste Pass system in KCD underground will be completed, with the potential of reducing
backfill costs and enabling the use of local contractors for haulage from surface waste dumps. In addition the Newtrax RFID tracking
system is planned to be implemented for underground equipment and personnel, providing cost benefits through automation of
secondary ventilation and improved equipment utilisation.
MINERAL RESOURCE
Details of average drill hole spacing and type in relation to Mineral Resource classification
Category
Spacing m (-x-)
Type of drilling
Diamond
RC
Blasthole
Channel
Other
Measured
5 x 10, 15 x 20
√
√
√
√
√
√
√
√
–
–
–
Indicated
40 x 40
–
–
–
Inferred
80 x 80
–
–
–
Grade/ore control
5 x 10, 15 x 20
–
–
–
57
SECTION 3 / CONTINENTAL AFRICA
KIBALI
CONTINUED
Inclusive Mineral Resource
as at 31 December 2018
Category
Tonnes
million
Grade
g/t
Contained gold
tonnes
Moz
Open pit
Measured
4.87
2.51
12.21
0.39
Indicated
14.53
2.12
30.81
0.99
Inferred
13.41
1.99
26.68
0.86
Total
32.80
2.13
69.70
2.24
Underground
Measured
3.27
8.44
27.58
0.89
Indicated
30.18
3.50
105.56
3.39
Inferred
10.36
3.16
32.72
1.05
Total
43.81
3.79
165.85
5.33
Stockpile
Measured
1.04
2.29
2.37
0.08
Indicated
–
–
–
–
Inferred
–
–
–
–
Total
1.04
2.29
2.37
0.08
Kibali
Total
77.65
3.06
237.93
7.65
Estimation
Mineral Resource estimation is undertaken by Barrick in-house Competent Persons or by approved external consultants. The results
of both DD and of RC drilling are used in the estimation process. 3D mineralised envelopes are established using grade and geology
and these are then statistically verified to confirm their validity for use in grade estimation.
Appropriate domaining of homogeneous zones is conducted whereby high-grade central core areas are modelled separately from
the lower-grade surrounding halos. Volumes are then filled with block model cells and these are then interpolated for density, rock
type and grade, the latter using ordinary kriging. Grade top cuts are applied to drill hole data to prevent the spread of high grades
during the estimation process. Drill hole spacing is used to guide the Mineral Resource classification. The open pit Mineral Resource
is quoted within a limiting shell. The underground Mineral Resource is constrained by the application of optimised mineable Mineral
Resource shapes, which applies reasonable mineability constraints including a minimum mining width, a reasonable distance from
current or planned development, and a measure of assumed profitability at the related Mineral Resource cut-off grade.
Grade tonnage curves
The grade tonnage curves do not include stockpiles.
58
SECTION 3 / CONTINENTAL AFRICA
Exclusive Mineral Resource
as at 31 December 2018
Category
Tonnes
million
Grade
g/t
Contained gold
tonnes
Moz
Kibali
Measured
1.42
2.68
3.81
0.12
Indicated
22.68
2.43
55.11
1.77
Inferred
23.77
2.50
59.40
1.91
Total
47.87
2.47
118.32
3.80
The exclusive Mineral Resource for the open pits largely comprise of Inferred Mineral Resource and tonnages that occur below the
Ore Reserve cut-off grade (due to gold price difference). At the KCD deposit it is also partially due to the selection of a fixed interface
between the open pit and the underground mining areas. Both the open pit Mineral Resource and underground material below the
Ore Reserve mining cut-off form a significant part of this material.
59
SECTION 3 / CONTINENTAL AFRICA
KIBALI CONTINUED
ORE RESERVE
Ore Reserve
as at 31 December 2018
Category
Tonnes
million
Grade
g/t
Contained gold
tonnes
Moz
Open pit
Proved
3.66
2.57
9.40
0.30
Probable
5.10
2.30
11.72
0.38
Total
8.75
2.41
21.12
0.68
Underground
Proved
5.48
5.20
28.48
0.92
Probable
13.99
4.79
66.98
2.15
Total
19.47
4.90
95.46
3.07
Kibali
Total
28.22
4.13
116.57
3.75
Estimation
The open pit Ore Reserve shell optimisations were completed on the Mineral Resource models. This incorporated the mining
layout, operating factors, stripping ratio and relevant cut-off grade and modifying factors for reporting the Ore Reserve. An open pit
underground interface was set at 5,685mRL between the KCD open pit and underground mine.
Kibali is very sensitive to a decrease in gold price
due to the nature of the underground mineralisation.
due to the nature of the underground mineralisation.
Year-on-year changes in Mineral Resource
Kibali was able to replace Mineral Resource ounces depleted as a result of the maiden reporting of the Kalimva and Ikamva open pit
Inferred Mineral Resource, as well as exploration extensions in KCD undergound.
Inclusive Mineral Resource sensitivity
60
SECTION 3 / CONTINENTAL AFRICA
A cut-off grade analysis at $1,000/oz was used to determine a cut-off grade of 2.5g/t for the underground mine. Longitudinal and
transverse longhole open stoping methods with paste backfill are the current preferred mining methods. Underground stope designs
were updated from the previously reported Ore Reserve using the latest Mineral Resource models. Modifying factors for planned
and unplanned rock dilution, backfill dilution and ore loss were applied to obtain the reported Ore Reserve.
Metallurgical, environmental, social, legal, marketing and economic factors were adequately considered in the Kibali FS and have
been updated as the project has developed.
Ore Reserve modifying factors
as at 31 December 2018
Gold
price
US$/oz
Cut-off
grade
g/t Au
Dilution
%
Dilution
g/t
MCF
%
MetRF
%
Open pit
1,000
1.53
10.0
–
103.0
84.5
Underground
1,000
2.41
4.0
1.0
103.0
88.9
$1,000/oz Ore Reserve price used by Barrick (operating partner), apart from KCD PB3 open pit which is at $1,100/oz
Open pit modifying factors include 10% ore dilution and 97% mining recovery.
Underground dilution was applied based on the proposed mining method and accounts for planned dilution, from internal waste,
within designed mining shapes. Additional dilution is incorporated to account for paste filling and unplanned dilution from mining (1%
to 13%). Ore loss of 4% is accounted for in the estimation of the final Ore Reserve.
Metallurgical recovery is applied to individual production sources and material types based on metallurgical testwork and historical
performance with recoveries ranging from 75% to 90% (2018 average recovery achieved was 88.7%).
The gold price applied to Ore Reserve estimation was $1,000/oz across all open pits and underground sources with the exception
of KCD PB3 open pit which was based on a gold price of $1,100/oz. A 4.5% royalty was netted off the assumed gold price.
Inferred Mineral Resource in business plan
There is no Inferred Mineral Resource included in the reported Ore Reserve for Kibali. The current mine plan does not have any
reliance on the Inferred Mineral Resource to support the economic viability of the project for the main KCD deposit.
The Ore Reserve decreased year-on-year mainly due to depletion, partially offset by exploration success in the underground and
conversion drilling in the KCD open pit.
Year-on-year changes in Ore Reserve
61
SECTION 3 / CONTINENTAL AFRICA
GHANA
AngloGold Ashanti has two mines
in Ghana. Obuasi, currently in
a redevelopment phase, is an
underground mine operating at
depths of up to 1,500m with a
continuous history of mining dating
back to the 1890s and Iduapriem, an
open pit mine.
in Ghana. Obuasi, currently in
a redevelopment phase, is an
underground mine operating at
depths of up to 1,500m with a
continuous history of mining dating
back to the 1890s and Iduapriem, an
open pit mine.
Obuasi underground development
is scheduled to start in Q1 2019
with first gold forecast for the end
of 2019.
is scheduled to start in Q1 2019
with first gold forecast for the end
of 2019.
Obuasi and Iduapriem are both
wholly owned by AngloGold
Ashanti. Obuasi is located in the
Ashanti region of southern Ghana,
approximately 80km south of
Kumasi. Mining was temporarily
suspended at the end of 2014
while a series of economic studies
progressed. Iduapriem is located in
western Ghana, some 85km from
the coast and south of Obuasi near
the town of Tarkwa.
wholly owned by AngloGold
Ashanti. Obuasi is located in the
Ashanti region of southern Ghana,
approximately 80km south of
Kumasi. Mining was temporarily
suspended at the end of 2014
while a series of economic studies
progressed. Iduapriem is located in
western Ghana, some 85km from
the coast and south of Obuasi near
the town of Tarkwa.
Ghana – Iduapriem
62
SECTION 3 / CONTINENTAL AFRICA
Inclusive Mineral Resource
as at 31 December 2018
Category
Tonnes
million
Grade
g/t
Contained gold
tonnes
Moz
Ghana
Measured
6.84
3.27
22.35
0.72
Indicated
184.26
4.08
750.93
24.14
Inferred
77.77
5.90
458.67
14.75
Total
268.87
4.58
1,231.95
39.61
Exclusive Mineral Resource
as at 31 December 2018
Category
Tonnes
million
Grade
g/t
Contained gold
tonnes
Moz
Ghana
Measured
3.51
5.57
19.55
0.63
Indicated
131.17
3.95
517.50
16.64
Inferred
75.01
6.09
456.79
14.69
Total
209.69
4.74
993.84
31.95
Ore Reserve
as at 31 December 2018
Category
Tonnes
million
Grade
g/t
Contained gold
tonnes
Moz
Ghana
Proved
2.74
0.88
2.41
0.08
Probable
56.66
4.07
230.82
7.42
Total
59.40
3.93
233.23
7.50
Project
Operation
LEGEND
1
Obuasi
2
Iduapriem
63
SECTION 3 / CONTINENTAL AFRICA
IDUAPRIEM
INTRODUCTION
Property description
Iduapriem Mine is wholly owned by AngloGold Ashanti. It is a multiple open pit operation that
currently sources ore from the Ajopa, Block 7 and Block 8 pits.
Location
Iduapriem Mine is located in the western region of Ghana, some 70km north of the coastal city
of Takoradi and approximately 10km southwest of the town of Tarkwa. The mine is bordered in
the north by Gold Fields Ghana Limited (Tarkwa Mine) and to the east by the Ghana Manganese
Company Limited (a manganese mine in existence since the 1920s).
History
A FS was completed in 1990 and in October 1991 Golden Shamrock Limited began construction of
a 1.36Mtpa semi-autogenous milling circuit and CIP plant. Mining commenced in August 1992 with
the first gold pour achieved in September of that year. Golden Shamrock was acquired by Ashanti
Goldfields Company Limited in 1996. In 2000, a portion of the non-operational Teberebie Goldfields
Limited (a subsidiary of Pioneer Goldfields Limited) was purchased resulting in increased Ore Reserve
and extended LOM. In 2002, Ashanti upgraded the plant capacity to 4Mtpa and in 2009 the plant
capacity was further extended to the current 5Mtpa.
Legal aspects and tenure
Iduapriem comprises the following mining leases:
•
Iduapriem LVB1539/89 covering 31km2 and expiring on 18 April 2019
•
Ajopa North LVB/WR326/09 covering 48.34km2 and expiring on the 5 January 2019
•
Teberebie LVB3722H/92 covering 25.83km2 and expired on 1 February 2018
All renewals had been suspended by the Regulator (the Minerals Commission), due to the ban on
small scale mining. The Minerals Commission will resume working through the backlog and renew
licence applications during the course of this year given that the ban was recently lifted.
A new Environmental Management Plan (EMP) has been submitted for the mining leases.
Mining method
Iduapriem is an open pit mine which makes use of contract miners. It uses conventional drill and
blast, with truck and excavator load and haul.
Operational infrastructure
Surface infrastructure associated with Iduapriem’s operation includes a primary crusher, overland
conveyor, CIP processing plant next to the main office building, tailings storage facility and two camp
areas for contractors and company employees. Tarkwa town is also adjacent to the tenement. Power
is obtained from the national grid.
Mineral processing
The current processing plant treats free-milling material from open-cast mining, by a conventional
crush-semi-autogenous ball milling circuit and leaching. Iduapriem operates a two stage crushing
circuit consisting of a 54-75 primary gyratory crusher and two GP550 gyratory crushers for
secondary crushing. The Iduapriem treatment plant has two semi-autogeneous grinding mills
(SAG mills) and two ball mills which run in two parallel circuits, each with a SAG mill and a ball mill.
Risks
Power reliability and stability, slope/high wall stability (rockfall potential) and inrush/inundation
(flooding of pits, tailing dams and infrastructure) are considered potential risks. Mitigation plans are in
place to manage these risks.
An independent external Mineral Resource and Ore Reserve audit was undertaken in 2018 and
found no fatal aws in process or output.
Competent Persons
Responsibility
Competent Person
Professional
organisation
Membership
number
Relevant
experience
Qualification
Mineral Resource
Charles Kusi-Manu
MAusIMM
205 238
28 years
BEng (Geological Engineering),
Postgraduate Certificate in
Geostatistics, MBA
Ore Reserve
Stephen Asante Yamoah MAusIMM
304 095
14 years
BSc Hons (Mining Engineering),
MSc (Mining Engineering)
64
SECTION 3 / CONTINENTAL AFRICA
Map showing Iduapriem Mine infrastructure and licences with the total mining lease area shown in the
top right-hand corner
top right-hand corner
Licences
Mining
Mine Infrastructure
Pits
Plant
ROM pad
Crusher
Stockpiles
Leach pad
TSF
Waste dumps
Settlements
Towns
Villages
Roads
Main
Secondary
Insert
Total mining lease area
Map zoomed in area
Plant centroid co-ordinates
2°02’38”W, 5°14’44”N
Total mining lease area
0
1
2
3km
0
2
4km
65
SECTION 3 / CONTINENTAL AFRICA
IDUAPRIEM CONTINUED
GEOLOGY
Iduapriem Mine is located within the Tarkwaian Group which forms part of the West African Craton that is covered to a large extent
by metavolcanics and metasediments of the Birimian Supergroup. In Ghana, the Birimian terrane consists of northeast-southwest
trending volcanic belts separated by basins and the Tarkwaian Group was deposited in these basins as shallow water deltaic
sediments. The Tarkwaian lithologies are considered to represent the erosion products that accumulated following the erosion of the
uplifted and deformed underlying Birimian rocks during the Eburnean orogeny. The basins (grabens) are believed to have formed as
a result of rifting, preferentially in the central parts of the Birimian volcanic belts. The Tarkwaian Group consists of a thick sequence
of clastic metasedimentary rocks which have undergone low grade regional metamorphism.
Deposit type
At Tarkwa, the entire Tarkwaian Group has been folded into a broad syncline and is locally referred to as the Tarkwa Syncline. The
Banket Series Formation comprises a sequence of individual quartz pebble conglomerates (Banket beds), breccia conglomerates
and metasandstones (also called quartzites and grits). All known gold mineralisation within the Banket Formation is associated
with the conglomerates and is found within the matrix that binds the pebbles together. Gold content is a function of the size and
amount (packing) of quartz pebbles present within a conglomeratic unit – the bigger and/or more pebbles present, the higher
the gold grade. The upper stratigraphic limit of the Banket Series Formation is marked by the hangingwall quartzite, siliceous
and metamorphosed sandstone of buff colour, which exhibits well-developed and characteristic trough- and cross-bedded
haematitic black sand banding. The hangingwall quartzite also contains thin discontinuous grit interbeds. Dykes and sills of doleritic
composition intrude the sedimentary sequence and frequently occur adjacent to complex structural zones. All gold mineralisation
generally occurs within four specific zones or reefs.
Mineralisation style
There are four recognised conglomerate reefs namely A, B, C and D which are equivalent to the Tarkwaian Sub-Basal, Basal (or
Main), Middle (or West) and Breccia Reefs respectively. The B and C reefs are oligomictic, and consist of well sorted conglomerates
and have been mined underground in some areas for over a century. The A and D reefs have a lower gold tenor and are polymictic
containing both well rounded and angular fragments.
Mineralisation characteristics
The gold is fine-grained, free milling and not associated with sulphides.
EXPLORATION
Exploration during 2018 focused on Mineral Resource conversion drilling at Block 7 and 8, Ajopa and Block 5 extension with
exploration target drilling at Mile 5W and traverse drilling at the TSF target. A total of 12,775m was drilled, comprising 9,988m DD
and 2,787m RC.
Geochemical results from lease-wide samples collected at Teberebie and Ajopa Leases were received with encouraging results.
A new mining lease, Ajopa South West, was traced to be in the name of Ghanaian Australian Goldfields (GAG). The change of name
was effected at the Mineral Commissions office to AngloGold Ashanti Iduapriem Limited and the renewal application was added to
the three existing mining leases awaiting final approval from the government.
Drilling in Block 5 extension intersected conglomerate reefs both along strike and down dip. Drill holes completed from the drilling
programme confirm the strike extension of the mineralisation. In all, 371m RC and 1,577m DD was drilled. Further to the north-
eastern portion of the target, drilling showed a reduction in the number of reefs along strike i.e. full reef packages A,B,C and D from
Block 5 pit margin gradually reduced to only one reef package along the 600m strike of the target.
66
SECTION 3 / CONTINENTAL AFRICA
A typical Geological section of Block 7 and 8, elevation in metres relative to average mean sea level
At Ajopa, sixteen holes were drilled totalling 819m RC and 3,029m DD. A total of 2,806 samples were generated from the drilling,
including duplicates and were submitted to SGS and Intertek laboratories. Two of the holes completed in the area at the start of
the drilling programme were for grade control to test reef duplications as well as down-dip extension of modelled reefs. Four of
the Mineral Resource drill holes were also attributed to sterilization and backfill projects. Sedimentological logs revealed well-packed
and well-sorted conglomerate reefs of C and B with sub- to well-rounded quartz pebbles with gold association beneath the planned
backfill pit limit.
The PFS drilling over the Block 7 and 8 area was undertaken during first half of the year, yielding 1,117m of samples by RC drilling
and 3,521m by DD. In all, 1,578 samples were submitted to the lab for gold analysis. All holes intersected the full conglomerate reef
package.
The Mile 5W drilling campaign yielded a total of 1,861m diamond drilling with 1,354 samples submitted for gold analysis. Some
interesting observations from the core include pink altered quartzite units with quartz veins and veinlets, disseminated pyrite
and sporadic euhedral shaped pyrrotites. The veins occur along the bedding with very few cross cut veins, all characterised by
tourmaline. The veins themselves rarely contain sulphides, showing only trace amounts of carbonates and sericite.
The TSF exploration drilling ended with a 10 hole RC drilling programme, totalling 480m. Some significant assays were reported.
The lithological units are mainly quartzites, with intercalated conglomeratic units.
Geochemical results from lease-wide soil samples collected at Teberebie and Ajopa Leases were received with encouraging results.
These will be reviewed and followed up with trenches in 2019.
The East Limb of Block 7 and 8 (near Johnson Mining) was inspected and may be tested for further exploration extensions.
PROJECTS
No major projects have recently been completed or are planned at Iduapriem. Geology projects planned include mine-wide
geochemical sampling, Mineral Resource drilling at Block 7 and 8, Ajopa and Block 5 extension.
Legend
D mineralised reef
C mineralised reef
B mineralised reef
A mineralised reef
Depleted pit
+1425
+1425
+1500
+1500
+1575
+1575
w
E
0
25
50
75
67
SECTION 3 / CONTINENTAL AFRICA
IDUAPRIEM CONTINUED
MINERAL RESOURCE
Details of average drill hole spacing and type in relation to Mineral Resource classification
Category
Spacing m (-x-)
Type of drilling
Diamond
RC
Blasthole
Channel
Other
Measured
20 x 15
–
√
√
√
√
√
√
–
–
–
Indicated
50 x 75
–
–
–
Inferred
100 x 100
–
–
–
Grade/ore control
20 x 15
–
–
–
–
In general 200 x 200m drill hole spacing is used to define the extent and geometry of an anomaly. The majority of the Mineral
Resource area has been drill tested at a spacing of a 100 x 100m with the spacing closed up to 50 x 50m for the shallower,
Indicated Mineral Resource.
The appropriate grid for each phase is optimised for each project based on the geometry of the mineralisation and the geological
and grade continuity (using variogram modelling) and mining experience from the pits.
In some cases, the data spacing may be reduced where structural complexity is encountered. Apart from the major fault structures,
geological continuity is considered to be very good with the conglomerate reefs being laterally consistent and continuous.
68
SECTION 3 / CONTINENTAL AFRICA
Inclusive Mineral Resource
as at 31 December 2018
Category
Tonnes
million
Grade
g/t
Contained gold
tonnes
Moz
Ajopa
Measured
–
–
–
–
Indicated
3.95
1.80
7.11
0.23
Inferred
0.49
2.31
1.14
0.04
Total
4.45
1.86
8.25
0.27
Block 1
Measured
–
–
–
–
Indicated
–
–
–
–
Inferred
0.23
1.69
0.39
0.01
Total
0.23
1.69
0.39
0.01
Block 3W
Measured
–
–
–
–
Indicated
6.83
1.17
7.99
0.26
Inferred
4.67
1.26
5.89
0.19
Total
11.50
1.21
13.88
0.45
Block 5
Measured
–
–
–
–
Indicated
5.15
1.19
6.10
0.20
Inferred
2.15
1.26
2.71
0.09
Total
7.30
1.21
8.82
0.28
Block 7 and 8 (other)
Measured
–
–
–
–
Indicated
34.26
1.61
55.03
1.77
Inferred
21.20
1.64
34.69
1.12
Total
55.46
1.62
89.72
2.88
Block 7 and 8 East cutback
Measured
–
–
–
–
Indicated
21.60
1.70
36.74
1.18
Inferred
0.12
1.29
0.15
0.00
Total
21.72
1.70
36.90
1.19
Stockpile (full grade ore)
Measured
2.74
0.88
2.41
0.08
Indicated
–
–
–
–
Inferred
–
–
–
–
Total
2.74
0.88
2.41
0.08
Stockpile (other)
Measured
–
–
–
–
Indicated
10.80
0.57
6.16
0.20
Inferred
2.76
0.68
1.88
0.06
Total
13.56
0.59
8.03
0.26
Stockpile (marginal ore)
Measured
0.59
0.66
0.39
0.01
Indicated
6.23
0.67
4.17
0.13
Inferred
–
–
–
–
Total
6.82
0.67
4.56
0.15
Iduapriem
Total
123.78
1.40
172.96
5.56
No geological discounts have been applied in the model. Dykes which sterilise mineralisation and faults which may offset
mineralisation are explicitly modelled.
Estimation
Geostatistical techniques are employed in the estimation of the Mineral Resource. 3D wireframes are built from all geological
information obtained from drill hole data, mapping of pits and geophysical data interpretations. Where appropriate these wireframes
are subdivided into the individual reef units that occur within a broad conglomerate package. Estimation is by ordinary kriging into
block sizes that range from 5 to 25m in the X and Y directions and between 6m and 12m in the Z direction depending on the reef
width and data spacing. Densities are allocated from appropriate test work conducted on drill hole samples. Grade and tonnages
are computed from these block models that are constrained within an optimised pit shell at the Mineral Resource reporting gold price.
Full grade ore and marginal stockpiles as well as Run of Mine (ROM) material are surveyed on a monthly basis to validate tonnage
measurements. Grade measurements on these stockpiles are based on RC grade control drilling from the individual pits mined.
69
SECTION 3 / CONTINENTAL AFRICA
IDUAPRIEM CONTINUED
During recent years, historic stockpiles were drilled and estimated using geostatistical techniques. These stockpiles were reported
as part of the Mineral Resource if material occurred above the economic cut-off grade at the Mineral Resource gold price.
The grade tonnage curve does not include stockpiles.
Exclusive Mineral Resource
as at 31 December 2018
Category
Tonnes
million
Grade
g/t
Contained gold
tonnes
Moz
Iduapriem
Measured
–
–
–
–
Indicated
52.41
1.38
72.22
2.32
Inferred
28.86
1.56
44.98
1.45
Total
81.27
1.44
117.20
3.77
The exclusive Mineral Resource is the part of the Mineral Resource that was not converted to Ore Reserve. It is defined as the
Mineral Resource that is outside the current Ore Reserve designs, but inside the Mineral Resource shells and includes the Inferred
Mineral Resource within the Ore Reserve design. The exclusive Mineral Resource gives an indication of the future potential of the
deposit. This material could be converted to Ore Reserve with an increase in the gold price and favorable costs. Exclusive Mineral
Resource also includes material within the pit between the Mineral Resource and Ore Reserve cut-offs.
Year-on-year changes include a decrease to the Mineral Resource as a result of depletion and increases as a result of cost and
exploration drilling reductions.
Year-on-year changes in Mineral Resource
Grade tonnage curve
70
SECTION 3 / CONTINENTAL AFRICA
ORE RESERVE
Ore Reserve
as at 31 December 2018
Category
Tonnes
million
Grade
g/t
Contained gold
tonnes
Moz
Ajopa
Proved
–
–
–
–
Probable
0.61
2.04
1.24
0.04
Total
0.61
2.04
1.24
0.04
Block 5
Proved
–
–
–
–
Probable
2.15
1.23
2.65
0.09
Total
2.15
1.23
2.65
0.09
Block 7 and 8 East cutback
Proved
–
–
–
–
Probable
21.48
1.68
36.03
1.16
Total
21.48
1.68
36.03
1.16
Stockpile (full grade ore)
Proved
2.74
0.88
2.41
0.08
Probable
–
–
–
–
Total
2.74
0.88
2.41
0.08
Stockpile (other)
Proved
–
–
–
–
Probable
5.26
0.74
3.88
0.12
Total
5.26
0.74
3.88
0.12
Stockpile (marginal ore)
Proved
–
–
–
–
Probable
6.89
0.67
4.62
0.15
Total
6.89
0.67
4.62
0.15
Iduapriem
Total
39.13
1.30
50.83
1.63
Estimation
The 3D Mineral Resource models are used as the basis for the Ore Reserve. A mineralisation envelope is developed using the
Mineral Resource block model, geological information and the relevant cut-off grade, which is then used for mine design. An
appropriate mining layout is designed that incorporates mining extraction losses and dilution factors.
The Ore Reserve is estimated within mine designs, based on modifying factors, based on actual mining and detailed analysis of cut-
off grade, geotechnical, environmental, productivity considerations and the requirements of the mining eet. The upper portions of
the Ajopa deposit have been discounted for the estimated depletion by artisanal miners. This discount factor has been derived from
observation and estimates based on the Mineral Resource model.
The Mineral Resource is highly sensitive to changes
in gold price due to the high stripping cost and
capital intensive cutbacks required to access the
deeper portions of the orebody.
in gold price due to the high stripping cost and
capital intensive cutbacks required to access the
deeper portions of the orebody.
Inclusive Mineral Resource sensitivity
71
SECTION 3 / CONTINENTAL AFRICA
Ore Reserve modifying factors
as at 31 December 2018
Gold
price
US$/oz
Cut-off
grade
g/t Au
RMF
% (based
on tonnes)
RMF
% (based
on g/t)
MRF
% (based
on tonnes)
MRF
% (based
on g/t)
MCF
%
MetRF
%
Ajopa
1,100
0.90
100.0
100.0
100.0
96.0
100.0
95.9
Block 5
1,100
0.85
100.0
100.0
100.0
96.0
100.0
95.9
Block 7 and 8 East cutback
1,100
0.85
100.0
100.0
100.0
96.0
100.0
95.9
Stockpile (full grade ore)
1,100
0.75
100.0
100.0
100.0
100.0
100.0
93.0
Stockpile (marginal ore)
1,100
0.55
100.0
100.0
100.0
100.0
100.0
93.0
Stockpile (other)
1,100
0.60
100.0
100.0
100.0
100.0
100.0
93.0
A mining recovery factor (MRF) of 96.0% was applied to the standard orebody models by reducing all block grades by 4.0% and
100% mining tonnage factor, which are based on reconciliation over a three-year period.
Inferred Mineral Resource in business plan
as at 31 December 2018
Tonnes
million
Grade
g/t
Contained gold
tonnes
Moz
Ajopa
0.02
2.30
0.04
0.00
Block 5
0.03
1.45
0.05
0.00
Block 7 and 8 East cutback
0.12
1.25
0.15
0.00
Total
0.17
1.39
0.24
0.01
Inferred Mineral Resource is included in the business plan. The overall Inferred Mineral Resource allowed for in the plan is
around 9%. However, only Measured and Indicated Mineral Resource within the design of the selected pit shells are converted to
Ore Reserve.
Year-on-year, the Ore Reserve was down as minor cost improvements failed to replace dilution.
IDUAPRIEM CONTINUED
Year-on-year changes in Ore Reserve
72
SECTION 3 / CONTINENTAL AFRICA
73
SECTION 3 / CONTINENTAL AFRICA
OBUASI
INTRODUCTION
Property description
Obuasi Gold Mine is owned and operated by AngloGold Ashanti Ghana Limited (AGAG). AGAG
was established following the merger of the former AngloGold Limited of South Africa and Ashanti
Goldfields Company Limited of Ghana in April 2004.
Production started in 1897 and stopped in the last quarter of 2014. Some aspects of the mine
continued under limited operational conditions, including the development of the underground decline.
A favourable FS was completed in 2017 and indicated a strong technical and economical case with
an anticipated 20-year mine life. In 2018 approval was received from the AngloGold Ashanti board to
proceed with the project with first gold planned for Q4 2019.
Location
Obuasi Gold Mine is located in the municipality of Obuasi, in the Ashanti region of Ghana, some
260km northwest of the capital Accra and 60km south of Kumasi.
History
Underground production was continuous from 1897 to 2014. A phase of open pit mining was
conducted from 1988 to 2000 with small intermittent open pit mining beyond that period. Total
historic production is ~33Moz gold, including ~5Moz gold from open pits.
Legal aspects and tenure
Obuasi gold mine concession previously covered an area of approximately 475km2 and had
80 communities within a 30km radius of the mine. This was reduced to 201.46km2 on 3 March 2016.
The majority of the reduced concession area falls in the Obuasi municipality.
Minor portions of the new concession fall in the Adansi North, Adansi South and Amansie
Central districts.
The Obuasi Gold Mine Mineral Resource and Ore Reserve is covered by a number of mining leases,
namely:
•
Obuasi Concession comprising 152.6km2
•
Binsere Concession parts 1, 2 and 3 comprising 48.86km2
The duration of the mining concessions, which expire on 5 March 2054, are covered by a stability
agreement with the government of Ghana.
Mining method
Mine designs are done to delineate development layouts and production stopes by taking into
consideration economic cut-off grade and geotechnical design parameters for each mining block,
mining level and section. The underground development extends to a depth of 1,500m from surface.
Mining levels lie between 15m and 20m intervals with major levels between 30m and 60m intervals.
Underground production was by open-stope mining (both longitudinal and transverse), and sub-level
caving method, with future designed production by longhole open-stope mining methods with paste
ll. Ore is transported to surface via shafts or trucked up the decline.
Operational infrastructure
Existing infrastructure includes a 2.4Mtpa processing plant with flotation and bacterial oxidation
(BIOX), underground development, hoisting shafts and associated infrastructure, power and water
reticulation, office complexes, workshops and company housing estates.
Mineral processing
The plant is configured for flotation and BIOX treatment that is required for the underground
refractory sulphide ore type.
Risks
The Obuasi Mine is currently embarking on a Redevelopment Project that aims to establish Obuasi
as a modern, efficient, mechanised, underground operation. This work is on-going with first gold
scheduled for the end of 2019.
The current Ore Reserve has been estimated based partially on the 2014/2015 Mineral Resource
and partially on the 2016/2017 Mineral Resource. Therefore, some of the significant changes to the
Mineral Resource resulting from the revised geological model and extensive data validation have
not yet rolled through to all parts of the Ore Reserve. This is seen as a small risk but is more likely to
represent a potential upside to the Ore Reserve.
74
SECTION 3 / CONTINENTAL AFRICA
Licences
Mining
Mine infrastructure
Pits
Plant
TSF
Waste dumps
Underground access
Ponds and dams
Consolidated operations footprint
Settlements
Towns
Villages
Roads
Main
Secondary
Airfield
0
2
4
6km
Plant centroid co-ordinates
1°41’16”W, 6°10’11”N
Map showing Obuasi Gold Mine infrastructure and licences
75
SECTION 3 / CONTINENTAL AFRICA
OBUASI CONTINUED
Competent Persons
Responsibility
Competent Person
Professional
organisation
Membership
number
Relevant
experience
Qualification
Mineral Resource
Richard Peattie
MAusIMM
301 029
18 years
BSc Hons (Geology), MSc (Mineral
Resource Evaluation)
Ore Reserve
Wayne Emslie
MAusIMM
211 371
23 years
BEng Hons (Mining)
GEOLOGY
Deposit type
The mine is located within the Obuasi concession area in south-western Ghana along the north-easterly-striking Ashanti volcanic
belt. The deposit is one of the most significant Proterozoic gold belts discovered to date. The Ashanti belt predominantly comprises
sedimentary and mafic volcanic rocks, and is the most prominent of the ve Birimian Supergroup gold belts found in Ghana.
The Birimian was deformed, metamorphosed and intruded by syn- and post-tectonic granitoids during the Eburnean tectonothermal
event around two billion years ago. Folding trends are dominantly north-northeast to north-east. Elongate syn- Birimian basins
developed between the ridges of the Birimian system and these were filled with the Tarkwaian molasse sediments made up primarily
of conglomerates, quartzose and arkosic sandstones and minor shale units. Major faulting has taken place along the same trends.
The Lower Birimian metasediments and metavolcanics are characterised and defined by argillaceous and fine to intermediate
arenaceous rocks. These rocks are represented by phyllites, metasiltstones, metagreywackes, tuffaceous sediments, ash tuffs
and hornstones in order of decreasing importance. Adjacent to the shear zones, these rocks are replaced by sericitic, chloritic and
carbonaceous schists, which may be graphitic in places. Multiple lodes are a common feature in the mine.
Granites outcrop in the west and north-west of the concession area and intrude the Birimian rocks only. Two types of granite are
present; one is more resistant to weathering than the other, with less-resistant granite being prospective for gold mineralisation.
Mineralised shears are found in close proximity to the contact with harder metamorphosed and metasomatically-altered intermediate
to basic Upper Birimian volcanics. The competency contrast between the harder metavolcanic rocks to the east and the more
argillaceous rocks to the west is thought to have formed a plane of weakness. During crustal movement, this plane became a zone
of shearing and thrusting coeval with the compressional phases.
Mineralisation style
Gold mineralisation is associated with, and occurs within, graphite-chlorite-sericite fault zones. These shear zones are commonly
associated with pervasive silica, carbonate and sulphide hydrothermal alteration and occur in tightly folded Lower Birimian schists,
phyllites metagreywackes, and tuffs, along the eastern limb of the Kumasi anticlinorium.
Mineralisation characteristics
Two main ore types are present, namely quartz vein and sulphide ore. The quartz vein type consists mainly of quartz with free gold
in association with lesser amounts of various metal sulphides containing iron, zinc, lead and copper. This ore type is generally non-
refractory. Sulphide ore is characterised by the inclusion of gold in the crystal structure of arsenopyrite minerals. Higher gold grades
tend to be associated with finer grain arsenopyrite crystals. Sulphide ore is generally refractory.
EXPLORATION
No exploration was done during the year.
PROJECTS
In 2014, a detailed FS began that considered the optimum mining methodology and schedules for the underground mine, based
on modern mechanised mining methods and refurbishment of underground, surface and process plant infrastructure. It was
recognised that a significant rationalisation and/or replacement of current infrastructure will enable the delivery of high utilisation
and productivity metrics.
During this time Obuasi operated in a limited operating phase with underground activities essentially restricted to continued
development of the Obuasi deeps decline and underground infill drilling. The limited operating phase was brought to a halt after an
incursion by illegal miners on Obuasi’s concession in February 2016. The mine has been under care and maintenance ever since.
76
SECTION 3 / CONTINENTAL AFRICA
N-S Geological cross-section through Obuasi Block 8, elevation in mRL
Legend
Mineralised lodes
Footwall lode 6 (FW06)
Footwall lode 7 (FW07)
Hangingwall lode 1 (HW01)
Obuasi ssure (OF05)
Geology
Graphitic Schist
Metavolcanics
Shear Vein Quartz
HW/FW shears
Sulphide Ore Zone
11222N
11022N
10822N
-800RL
-600RL
-400RL
-200RL
0RL
200RL
10622N
10822N
11022N
11222N
200RL
0RL
-200RL
-400RL
-600RL
-800RL
N
S
0m
100m
Scale: 1:3,000
77
SECTION 3 / CONTINENTAL AFRICA
OBUASI CONTINUED
The FS was finalised in March 2016, with a schedule for the potential restart of underground production. The FS was followed up
with an optimised FS that looked at reducing capital spend upfront. This was finalised at the end of 2017. In 2018 approval was
received from the AngloGold Ashanti board for project commencement.
Obuasi is currently embarking on the process of rebuilding the mine in all its aspects to deliver a modern, efficient, mechanised,
underground operation.
Underground development is scheduled to start in Q1 2019 with first gold forecast for the end of 2019.
MINERAL RESOURCE
Details of average drill hole spacing and type in relation to Mineral Resource classification
Category
Spacing m (-x-)
Type of drilling
Comments
Diamond
RC
Blasthole
Channel
Other
Measured
20 x 20
√
√
√
√
–
√
√
√
√
–
–
–
Indicated
60 x 60
–
–
–
–
Inferred
90 x 90, 120 x 120
–
–
√
–
–
Grade/ore control
10 x 10
–
–
Channel sampling of
cross-cuts
78
SECTION 3 / CONTINENTAL AFRICA
Inclusive Mineral Resource
as at 31 December 2018
Category
Tonnes
million
Grade
g/t
Contained gold
tonnes
Moz
Anyankyirem
Measured
–
–
–
–
Indicated
5.52
2.38
13.10
0.42
Inferred
0.09
2.71
0.24
0.01
Total
5.61
2.38
13.35
0.43
Anyinam
Measured
0.00
2.50
0.01
0.00
Indicated
0.45
3.54
1.59
0.05
Inferred
1.02
4.23
4.32
0.14
Total
1.47
4.02
5.92
0.19
Gyabunsu – Sibi
Measured
0.05
4.00
0.21
0.01
Indicated
0.05
3.48
0.16
0.01
Inferred
0.28
3.97
1.13
0.04
Total
0.38
3.92
1.50
0.05
Above 50 Level – Block 1
Measured
–
–
–
–
Indicated
10.29
5.16
53.10
1.71
Inferred
2.04
5.08
10.36
0.33
Total
12.33
5.15
63.46
2.04
Above 50 Level – Block 2
Measured
–
–
–
–
Indicated
8.69
5.94
51.61
1.66
Inferred
2.83
5.91
16.72
0.54
Total
11.52
5.93
68.32
2.20
Above 50 Level – Block 8
Measured
1.83
4.46
8.14
0.26
Indicated
29.72
5.65
168.02
5.40
Inferred
3.78
5.75
21.69
0.70
Total
35.32
5.60
197.86
6.36
Above 50 Level – Block 10
Measured
–
–
–
–
Indicated
21.20
6.09
129.08
4.15
Inferred
5.06
5.82
29.49
0.95
Total
26.26
6.04
158.57
5.10
Above 50 Level – Adansi
Measured
–
–
–
–
Indicated
5.48
14.52
79.59
2.56
Inferred
1.81
14.31
25.89
0.83
Total
7.29
14.47
105.49
3.39
Above 50 Level – Côte d’Or
Measured
–
–
–
–
Indicated
0.01
18.03
0.19
0.01
Inferred
13.85
10.75
148.84
4.79
Total
13.86
10.76
149.03
4.79
Above 50 Level – Sansu
Measured
1.63
6.87
11.18
0.36
Indicated
9.27
5.29
49.04
1.58
Inferred
2.61
5.41
14.09
0.45
Total
13.51
5.50
74.31
2.39
Below 50 Level – Block 11
Measured
–
–
–
–
Indicated
3.26
21.51
70.19
2.26
Inferred
4.48
17.15
76.84
2.47
Total
7.74
18.99
147.03
4.73
Below 50 Level – Block 14
Measured
–
–
–
–
Indicated
1.50
7.95
11.96
0.38
Inferred
8.30
7.50
62.20
2.00
Total
9.80
7.56
74.16
2.38
Obuasi
Total
145.10
7.30
1,058.99
34.05
ESTIMATION
From 2016 to 2018, an exhaustive process of data review and validation took place, as well as capture of historic geological
79
SECTION 3 / CONTINENTAL AFRICA
OBUASI CONTINUED
information. Together, this has considerably increased the confidence of the input data and supported a refinement of the Mineral
Resource models. The geological interpretation is based on DD, cross-cut sampling and underground mapping information. Block
models are estimated within the delineated mineralised ore zones using ordinary kriging. Estimates at Obuasi are based on a block
model comprised of 20 x 5 x 15m blocks, which approximates the minimum SMU for underground mining.
The open pit Mineral Resource at Obuasi was estimated by geostatistical techniques within 3D wireframe models of the
mineralisation. These models are based on geological information and cut-off boundaries defined by sampling results. Geological
interpretation is based on trench sampling and RC and/or DD. Estimation is by ordinary kriging into 30 x 30 x 10m blocks for Obuasi
open pits.
Obuasi uses the 15% rule with 90% confidence to classify its Mineral Resource into Measured, Indicated and Inferred Mineral
Resource.
Exclusive Mineral Resource
as at 31 December 2018
Category
Tonnes
million
Grade
g/t
Contained gold
tonnes
Moz
Obuasi
Measured
3.51
5.57
19.55
0.63
Indicated
78.76
5.65
445.28
14.32
Inferred
46.14
8.93
411.82
13.24
The exclusive Mineral Resource is made up of Mineral Resource from underground and open pit. The bulk of the exclusive Mineral
Resource is from underground, and is spread across the entire deposit, where further study and design, change in costs and/or
gold price is required to develop economic extraction plans.
37% of the exclusive Mineral Resource is Inferred Mineral Resource and will require upgrading of its confidence to be able to report
as an Ore Reserve.
Mineral Resource below infrastructure
as at 31 December 2018
Category
Tonnes
million
Grade
g/t
Contained gold
tonnes
Moz
Obuasi
Measured
–
–
–
–
Indicated
4.77
17.23
82.15
2.64
Inferred
12.78
10.88
139.04
4.47
Total
17.55
12.61
221.19
7.11
Mineral Resource below infrastructure is from those areas below 50 Level. These areas have been extensively drilled but no
infrastructure is currently in place to exploit.
Grade tonnage curves
80
SECTION 3 / CONTINENTAL AFRICA
With no new mining or geological information collected during the year the Mineral Resource has remained constant from
year to year.
Obuasi is very sensitive to changes in gold price,
especially to a lower gold price, due to the lower
grade sulphide mineralisation on the flanks of the
high grade quartz.
especially to a lower gold price, due to the lower
grade sulphide mineralisation on the flanks of the
high grade quartz.
Year-on-year changes in Mineral Resource
Inclusive Mineral Resource sensitivity
81
SECTION 3 / CONTINENTAL AFRICA
OBUASI CONTINUED
ORE RESERVE
Ore Reserve
as at 31 December 2018
Category
Tonnes
million
Grade
g/t
Contained gold
tonnes
Moz
Above 50 Level – Block 1
Proved
–
–
–
–
Probable
0.91
6.49
5.91
0.19
Total
0.91
6.49
5.91
0.19
Above 50 Level – Block 2
Proved
–
–
–
–
Probable
1.35
6.08
8.22
0.26
Total
1.35
6.08
8.22
0.26
Above 50 Level – Block 8
Proved
–
–
–
–
Probable
7.24
8.16
59.04
1.90
Total
7.24
8.16
59.04
1.90
Above 50 Level – Block 10
Proved
–
–
–
–
Probable
6.42
7.28
46.73
1.50
Total
6.42
7.28
46.73
1.50
Above 50 Level – Adansi
Proved
–
–
–
–
Probable
0.74
16.60
12.36
0.40
Total
0.74
16.60
12.36
0.40
Above 50 Level – Côte d’Or
Proved
–
–
–
–
Probable
0.01
16.47
0.10
0.00
Total
0.01
16.47
0.10
0.00
Above 50 Level – Sansu
Proved
–
–
–
–
Probable
1.91
7.80
14.89
0.48
Total
1.91
7.80
14.89
0.48
Below 50 Level – Block 11
Proved
–
–
–
–
Probable
1.70
20.68
35.15
1.13
Total
1.70
20.68
35.15
1.13
Obuasi
Total
20.28
9.00
182.40
5.86
Estimation
3D Mineral Resource models are used as the basis for the Ore Reserve evaluation. Using the Mineral Resource block model, a
mineralisation envelope is developed by applying the relevant cut-off grade, which is then used for a mine design. An appropriate
mining layout is designed that incorporates mining extraction losses and dilution factors.
All mine designs are done to delineate stopes by taking into consideration cut-off grade, geotechnical design parameters for
each mining block, ventilation and backfill requirement, mining level and section, usually leading to an optimisation of the existing
infrastructure, mining sequence, and corresponding development layouts. The underground operation runs to a depth of 1,500m
from surface. Mining levels are between 15m and 20m intervals with major levels between 30m and 60m intervals. Underground
production mining methods include both longitudinal and transverse open stoping.
The current Ore Reserve has been estimated based partially on the 2014/2015 Mineral Resource and partially on the 2016 Mineral
Resource. The significant changes to the Mineral Resource, resulting from the revised geological model and extensive data
validation, have not impacted the entire Ore Reserve with only the southern blocks re-designed to the 2016 Mineral Resource.
The blocks re-designed during 2017 include: Sansu, Block 8 and Block 10 (includes Block 9). The remaining blocks will be
redesigned during 2019.
Ore Reserve modifying factors
82
SECTION 3 / CONTINENTAL AFRICA
as at 31 December 2018
Gold
price
US$/oz
Cut-off
grade
g/t Au
Dilution
%
MRF
% (based
on tonnes)
MRF
% (based
on g/t)
MCF
%
MetRF
%
Above 50 Level – Adansi
1,100
5.20
14.0
98.0
100.0
100.0
87.0
Above 50 Level – Block 1
1,100
4.20
16.0
96.0
100.0
100.0
87.0
Above 50 Level – Block 2
1,100
4.30
15.0
96.0
100.0
100.0
87.0
Above 50 Level – Block 8
1,100
4.10
15.0
96.0
100.0
100.0
87.0
Above 50 Level – Block 10
1,100
4.25
10.0
96.0
100.0
100.0
87.0
Above 50 Level – Côte d’Or
1,100
5.00
5.0
100.0
100.0
100.0
87.0
Above 50 Level – Sansu
1,100
4.10
15.0
95.0
100.0
100.0
87.0
Below 50 Level – Block 11
1,100
5.20
16.0
96.0
100.0
100.0
87.0
Several factors are used for the modifying of the Ore Reserve and include mining recovery, dilution and processing recovery. These
are applied based on the mining method employed. A weighted average dilution factor equal to 15.5% is for all of the Ore Reserve.
Inferred Mineral Resource in business plan
83
SECTION 3 / CONTINENTAL AFRICA
OBUASI CONTINUED
84
SECTION 3 / CONTINENTAL AFRICA
as at 31 December 2018
Tonnes
million
Grade
g/t
Contained gold
tonnes
Moz
Above 50 Level – Block 1
0.01
6.36
0.09
0.00
Above 50 Level – Block 2
0.67
6.70
4.49
0.14
Above 50 Level – Block 8
0.54
5.96
3.23
0.10
Above 50 Level – Block 10
0.20
8.08
1.58
0.05
Above 50 Level – Adansi
0.09
8.01
0.72
0.02
Above 50 Level – Côte d’Or
2.55
6.66
17.01
0.55
Below 50 Level – Block 11
1.01
14.84
15.02
0.48
Total
5.08
8.30
42.13
1.35
With appropriate caution, a portion of the Inferred Mineral Resource was included in the business plan during the optimisation
process. This accounts for 20% of the business plan. The planned mining of Inferred Mineral Resource in the business plan is mainly
at the end of the LOM and has an exploration programme attached to it to ensure the upgrade to Indicated Mineral Resource. This
conversion of Inferred to Indicated Mineral Resource has taken into consideration historic conversion outcomes.
Ore Reserve below infrastructure
as at 31 December 2018
Category
Tonnes
million
Grade
g/t
Contained gold
tonnes
Moz
Obuasi
Proved
–
–
–
–
Probable
1.70
20.68
35.15
1.13
Total
1.70
20.68
35.15
1.13
Ore Reserve below infrastructure is restricted to the ground below 50 Level that requires a decline to access and is located between
50 and 60 Level below the Kwesi Mensah Shaft (KMS).
No mining or redesign occurred in 2018 as the mine remained on care and maintenance. The Ore Reserve figure remains as it was
in 2017.
Year-on-year changes in Ore Reserve
85
SECTION 3 / CONTINENTAL AFRICA
GUINEA
Siguiri Gold Mine is AngloGold
Ashanti’s only operation in the
Republic of Guinea. The mine is
85% owned by AngloGold Ashanti
and 15% by the government
of Guinea. The mine is a
conventional open pit operation
situated in the Siguiri-district in
the north-east of Guinea. It lies
about 850km north-northeast
from the capital city of Conakry
and 109km west of the border
with Mali by road.
Gold-bearing ore is mined from
several pits (generally three
pits at any one time). The plant
upgrade has been completed and
will ramp up during 2019.
Guinea – Siguiri
86
SECTION 3 / CONTINENTAL AFRICA
Inclusive Mineral Resource
as at 31 December 2018
Category
Tonnes
million
Grade
g/t
Contained gold
tonnes
Moz
Guinea
Measured
20.36
0.63
12.89
0.41
Indicated
164.46
0.87
143.58
4.62
Inferred
71.93
0.93
66.84
2.15
Total
256.75
0.87
223.30
7.18
Exclusive Mineral Resource
as at 31 December 2018
Category
Tonnes
million
Grade
g/t
Contained gold
tonnes
Moz
Guinea
Measured
–
–
–
–
Indicated
97.67
0.87
85.03
2.73
Inferred
71.93
0.93
66.84
2.15
Total
169.60
0.90
151.87
4.88
Ore Reserve
as at 31 December 2018
Category
Tonnes
million
Grade
g/t
Contained gold
tonnes
Moz
Guinea
Proved
21.54
0.67
14.40
0.46
Probable
59.40
0.84
49.82
1.60
Total
80.94
0.79
64.22
2.06
0
200km
LEGEND
1
Siguiri (85%)
Operation
87
SECTION 3 / CONTINENTAL AFRICA
SIGUIRI
INTRODUCTION
Property description
Siguiri in Guinea is 85% owned by AngloGold Ashanti and 15% by the government of Guinea. It is an
open pit operation.
Location
The mine is located approximately 850km north-northeast of Conakry, 25km northwest of the town
of Siguiri and 190km southeast of the Malian capital Bamako, near the Mali border.
History
Gold mining in the district can be traced back for centuries, but there are no reliable records of
pre-western production. The French became involved in the area in the late-19th and early-20th
centuries. Between 1931 and 1951, the French reported gold coming out of Siguiri, with figures
varying between 1t and 3.8t annually, however, little exploration work was completed.
There was a phase of Russian exploration in the area between 1960 and 1963 which focused on the
placer deposits along the major river channels.
In 1980, Société Minière Internationale du Quebéc (SOMIQ) gained the exploration rights for Siguiri
and Mandiana. SOMIQ focused its work on the Koron and Didi areas. The Chevaning Mining
Company Limited was then created to undertake a detailed economic evaluation of the prospect,
with more intensive work beginning in the late 1980s.
Société Aurifere de Guinea took over from its predecessors and continued work on the placer
deposits. Production on the Koron placer reached a peak in 1992 with 1.1t of gold being produced.
Due to a number of dif culties, the mine was shut down later that year. Golden Shamrock started a
FS in 1995 after which Ashanti Goldfields invested in the deposit and Siguiri mine started production
in 1998 as Société Ashanti Goldfields de Guinea (SAG).
The metallurgical plant is currently being upgraded to process hard rock and this is planned for
completion in Q1 2019.
Legal aspects and tenure
Siguiri is mined under licence from the government of Guinea. The published Mineral Resource and
Ore Reserve are covered by SAG mining concession D/97/171/PRG/SGG, totalling 1,494.5km2.
The original SAG concession was granted under the Convention de Base between the Republique
de Guinea and SAG signed on 4 August 1997. The concession is to be explored and mined
exclusively for gold, silver and diamonds by SAG for 25 years from the date of the agreement, until
4 August 2022. An updated concession was negotiated with the government in 2016.
The Convention de Base will guide the renewal of the mining concession in 2022. The SAG
concession was granted under a new amended Convention de Base between the Republique de
Guinea and SAG signed on 28 June 2016 and ratified by the Guinean parliament on 13 December
2016. The Convention de Base has been ratified by the constitutional court and published in the
Journal Officiel of the Republic of Guinea on 24 January 2017. Dependent on the submission of the
necessary renewal documentation on, or before, 4 March 2022 the concession is to be explored and
mined exclusively for gold, silver and diamonds by SAG for 25 years from the date of agreement to
13 December 2041.
Mining method
Siguiri is currently a multi-pit oxide gold mining operation, operated by a contract miner. The mining
method is selective conventional techniques using excavators and trucks on 3m high itches. Three
Caterpillar 6020B excavators are the main loading equipment matched with CAT 777G dump trucks.
A SMU suitable for selective mining and nominated mining equipment of 5 x 5 x 3m based on
historical grade control areas are used to simulate the expected mining dilution and ore losses.
Operational infrastructure
The Siguiri Gold Mine includes a processing plant, a TSF and other infrastructure such as a mine
village, water supply system, roads, power supply by on site generators and communications
systems. Additional infrastructure includes on site offices, accommodation and workshops to
support remote mining.
Siguiri can be accessed via a small airfield and a well-paved road connects Siguiri to Bamako in
the north and Kouroussa in the south. Access to the mine via roads and to Siguiri is easily passable
through most of the year, although some secondary roads are seasonal with limited access during
wet season.
88
SECTION 3 / CONTINENTAL AFRICA
Mineral processing
Processing of the ore is done by a CIP processing plant that has been successfully optimised to
reach an average throughput of 11.8Mt per annum. Ore has historically been derived from a number
of oxide pits in the Block 1 concession area with the primary future ore supply provided by existing
stockpiles (oxide ore), Kami and Bidini (both fresh rock ore).
The original processing facility was designed for the processing of soft ore only and can only
introduce a small percentage of fresh rock ore in the mill feed. A new ball mill and 3 stage crushing
plant capable of treating 50% hard ores was added to the circuit in 2018. The leach circuit has also
been converted to a hybrid CIL circuit.
Risks
Risks associated with the validity of the Siguiri mining concession and mining convention post 2018,
have been addressed by the favourable conclusion of the Convention de Base negotiation during
2016 and its ratification in 2017 by parliament. The current mining concession is confirmed to be
valid until 4 August 2022, with high likelihood of renewal until 2041.
The favourable conclusion of the Convention de Base negotiation during 2016 and its ratification
in 2017 by parliament has significantly reduced the risk of the remaining Mineral Resource and
Ore Reserve not being covered by a valid mining concession. The current mining concession is now
confirmed to be valid until 4 August 2022, with high likelihood of renewal until 2041.
Map showing Siguiri Gold Mine infrastructure, concession and exploration licences, Block 1 to Block 4
Licences
Mining
Exploration
Mine Infrastructure
Pits
Plant
ROM pad
Stockpiles
Leach pad
TSF
Waste dumps
Settlements
Towns
Villages
Deposit
Roads
Main
Secondary
0
10
20
30km
Plant centroid co-ordinates
9°23’27”W, 11°33’54”N
89
SECTION 3 / CONTINENTAL AFRICA
SIGUIRI CONTINUED
Competent Persons
Responsibility
Competent Person
Professional
organisation
Membership
number
Relevant
experience
Qualification
Mineral Resource
Steven Robins
MAusIMM
222 533
22 years
BSc Hons (Geology), MSc (Mineral
Resource Evaluation), MBA
Ore Reserve
Desiderius Kamugisha
MAusIMM
227 181
17 years
BSc (Mining Engineering)
GEOLOGY
The Siguiri Gold Mine is situated in the northern part of the Siguiri Basin of Guinea, and is underlain by Lower Proterozoic rocks
of the Birimian metasedimentary and volcano-sedimentary formations. Where exposed, the sediments consist of a well-bedded
turbiditic sequence of greenschist facies siltstones, sandstones, greywackes and minor conglomerates, with some brecciated and
possibly volcanic members. Stratigraphic relationships in the area are however, poorly understood due to poor exposure and a thick
lateritic duricrust.
of the Birimian metasedimentary and volcano-sedimentary formations. Where exposed, the sediments consist of a well-bedded
turbiditic sequence of greenschist facies siltstones, sandstones, greywackes and minor conglomerates, with some brecciated and
possibly volcanic members. Stratigraphic relationships in the area are however, poorly understood due to poor exposure and a thick
lateritic duricrust.
The typical regolith or laterite residual profile at Siguiri consists of four main sub-horizontal layers:
•
Lateritic duricrust: a hard ferruginous (and aluminous) crust
•
Mottled zone: a bauxite clay zone, produced by isovolumetric weathering, containing lateritic and gibbsitic nodules and
accumulations which impart a mottled appearance
•
Saprolite: a generally clay rich zone of weathered rock, composed of mixtures of kaolinite, hematite and/or goethite and/or
gibbsite. Although more than 20% of weatherable minerals are altered, primary fabrics are often preserved
•
Saprock/transition zone: slightly weathered rock with less than 20% of weatherable minerals altered
Map showing Siguiri Gold Mine infrastructure, concession and exploration licences, Block 1
0
2
4
8km
Plant centroid co-ordinates
9°23’27”W, 11°33’54”N
Licences
Mining
Exploration
Mine Infrastructure
Pits
Plant
ROM pad
Stockpiles
Leach pad
TSF
Waste dumps
90
SECTION 3 / CONTINENTAL AFRICA
The main structural and lithological trend in the current mining area of Block 1, changes from a roughly north-south orientation in the
south to northwest-southeast in the north.
The mineralisation at Siguiri occurs as a secondary gold in alluvial or colluvial gravel in lateritic cover and a primary vein hosted
mineralisation. The veins are quartz dominant and display a variety of styles and orientations, with a sub-vertical northeast-trending
conjugate quartz vein set predominating in most of the open pits, irrespective of the orientation of the bedding. Auriferous quartz
veins show a strong lithological control and are best developed in the sandstone/greywacke units.
The geology of Block 2 differs from Block 1 in that the block is mostly underlain by metavolcanics and volcanoclastics. Mineralisation
styles appear to be similar to those in Block 1, with Saraya appearing to be located on a north-south orientated structure.
Deposit type
The Siguiri orebodies are early Proterozoic (Birimian) orogenic quartz-vein hosted deposits located in the Siguiri Basin of West
Africa. Generally poorly exposed, the basin sediments have been subject to greenschist facies metamorphism and consist of a
well-bedded turbiditic sedimentary sequence with some brecciated and possibly volcanic members. Mineralisation also occurs as
secondary gold in alluvial and colluvial gravels in laterite cover.
Three main sedimentary packages are recognised in the Siguiri district, the Balato, Fatoya and Kintinian Formations. The Balato
Formation is dominated by centimetre scale alternations of shale-siltstone and greywacke. The overlying Fatoya Formation consists
of metre scale beds of greywacke ning towards the west.
The Kintinian Formation is a thick package of shale and sandstone with a basal clast-supported conglomerate.
The orebodies are structurally controlled and the area has undergone at least three distinct phases of deformation, with initial
north-south compression developing minor folds, the second and largest deformation event is associated with east-west to east-
northeast-west-southwest directed compression leading to north-south structural architecture, and the third event was a northwest-
southeast compression that led to refolding of existing structures.
A deep oxidation (weathering) profile is developed in the region, varying between 50 to 150m. The mineralised saprolite currently
provides the main oxide feedstock for the CIP processing plant although a new treatment option is nearing completion to process
the fresh rock extensions of the ore deposits.
Mineralisation style
Primary gold mineralisation occurs in all three lithostratigraphic units of the Siguiri region although most of the known mineralisation
is found in the central and more competent Fatoya Formation. In some deposits, the mineralisation shows strong lithological control
and is preferentially developed in coarser-grained units that have higher fracture/vein densities relative to fine-grained rocks.
The mineralisation dominantly follows sub-vertical north-south thrusts, northeast-southwest dextral shear zones, and west-
northwest to east-southeast sinistral faults associated with the main (D2) deformation event. The mineralised veins are remarkable
for the relative consistency of their orientation (northeast), despite the highly variable orientation of bedding and major structures.
Mineralised veins are more intensely developed along major structural trends with quartz-carbonate-sulphide veining developed
along structures. Some of these structures have developed as incipient faults and are represented by discrete stockworks of
mineralised quartz-carbonate veins occurring along a trend, instead of being clearly defined continuous structures.
Mineralisation characteristics
Two styles of primary mineralisation have been recognised at Siguiri. The first is characterised by precipitation of gold-bearing pyrite
associated with proximal albite and distal carbon alteration, and opening of carbonate-pyrite veins. The second style corresponds
to east-northeast to west-southwest trending native gold bearing quartz veins with carbonate selvages which crosscut carbonate-
pyrite veins and show arsenopyrite (pyrite) halos.
91
SECTION 3 / CONTINENTAL AFRICA
SIGUIRI CONTINUED
EXPLORATION
Exploration at Siguiri was historically focused on nding new oxide Mineral Resource in the saprolite and upgrading the confidence
in the existing oxide Mineral Resource. This was achieved using geophysics, soil geochemistry and drill hole sampling in the context
of the regional and pit-scale geological models. Following the completion of an asset strategy optimisation project in 2012, which
indicated the potential economic viability of the fresh rock material, the aim of the exploration has expanded and the objectives are
two-fold. Firstly, to explore for replacement and additional oxide material for short-term mining requirements. Secondly, to increase
the level of confidence in the ve major fresh rock targets below the existing oxide pits at Kami, Bidini, Tubani, Ségulén, Sokunu
and Sintroko.
1,504 drill holes totalling 87,013m were completed in 2018 and primarily focused (51%) on increasing confidence in the Saraya, and
Foulata Mineral Resource to generate Indicated Mineral Resource in support of the Remote Lease PFS project at Block 2.
Infill drilling comprising 23% of the total drilling occurred on Block 1 over various deposits (Kami, Tubani, Silakoro, Sintroko, Kozan
North Bidini West and Eureka North). Reconnaissance drilling comprised 19% of the total metres and was focused on depth
extensions at Seguélén, Sokunu, and Kosise, while new oxide targets were drilled at Foulata East (Block 2) and the Saraya West,
Corridor and TSF Exploration Licences. The remaining 7% of total metres comprised sterilisation drilling at Silakoro.
Target generation and evaluation of Block 4, was completed during 2018 and an AC reconnaissance drill programme initiated in
December 2018.
W-E Geological cross-section of the Kami deposit, elevation in metres relative to average mean sea level
PROJECTS
A FS to allow the exploitation of the fresh rock material was completed in December 2015. Called the combination plant project, it
will upgrade the current plant and enable processing of a combination of oxides and fresh rock material. The plant throughput will
remain at 12Mtpa with a exible design allowing up to 6Mtpa fresh rock material to be processed. Targeted fresh rock pits include
Kami, Bidini, Tubani, Sintroko, Seguélén and Sokuno. The FS was approved by the board of AngloGold Ashanti following successful
negotiations with the government of Guinea regarding the Convention de Base and having obtained access to Seguélén Area 1.
Construction of the combination plant commenced in 2017 and will be completed during Q1 of 2019.
Fatoya Formation – coarse/medium
grained greywacke dominant
grained greywacke dominant
Fatoya Formation – fine grained
siltstone dominated
siltstone dominated
Balato Formation –
ne grained siltstone, shale, black shale
Orebody
Fault
Fold axis
Oxide – fresh rock transition
Legend
92
SECTION 3 / CONTINENTAL AFRICA
Conceptual studies were initiated to evaluate the potential of mining in Block 2 and Block 3 with priority placed on the higher value
Block 2 deposits. Infill drilling, aimed to convert Inferred to Indicated Mineral Resource was completed at Foulata and Saraya in
2018, culminating in the start of a PFS in the second half of 2018 and completion in early 2019.
MINERAL RESOURCE
Details of average drill hole spacing and type in relation to Mineral Resource classification
Category
Spacing m (-x-)
Type of drilling
Comments
Diamond
RC
Blasthole
Channel
Other
Measured
–
√
√
√
√
√
√
√
–
–
–
–
Indicated
25 x 25 (square or
staggered) and 50 x 25
(Kami and Bidini)
–
–
–
–
Inferred
20 x 40, 50 x 25, 50 x 50
–
–
–
–
Grade/ore control
5 x 10, 5 x 12, 10 x 5,
10 x 10, 13 x 7, 13 x 8
–
–
–
Variable
dependent
on the deposit
and continuity of
mineralisation
In general, 100 x 200m drill hole spacing is used to define the extent and geometry of anomalies.
93
SECTION 3 / CONTINENTAL AFRICA
SIGUIRI CONTINUED
Inclusive Mineral Resource
as at 31 December 2018
Category
Tonnes
million
Grade
g/t
Contained gold
tonnes
Moz
Bidini (fresh rock)
Measured
–
–
–
–
Indicated
8.02
1.44
11.57
0.37
Inferred
1.95
1.39
2.70
0.09
Total
9.97
1.43
14.27
0.46
Bidini (oxide)
Measured
–
–
–
–
Indicated
3.15
0.90
2.84
0.09
Inferred
7.30
0.82
6.00
0.19
Total
10.45
0.85
8.83
0.28
Bidini (transitional)
Measured
–
–
–
–
Indicated
3.63
1.48
5.37
0.17
Inferred
0.76
1.46
1.10
0.04
Total
4.39
1.47
6.47
0.21
Eureka East
Measured
–
–
–
–
Indicated
0.69
0.92
0.63
0.02
Inferred
0.23
0.77
0.18
0.01
Total
0.92
0.88
0.81
0.03
Eureka North
Measured
–
–
–
–
Indicated
1.63
0.85
1.38
0.04
Inferred
0.97
1.06
1.03
0.03
Total
2.60
0.93
2.41
0.08
Foulata
Measured
–
–
–
–
Indicated
3.83
1.31
5.02
0.16
Inferred
0.59
1.50
0.88
0.03
Total
4.42
1.34
5.90
0.19
Kalamagna
Measured
–
–
–
–
Indicated
5.90
0.71
4.17
0.13
Inferred
2.66
0.68
1.79
0.06
Total
8.56
0.70
5.96
0.19
Kami (fresh rock)
Measured
–
–
–
–
Indicated
35.21
0.96
33.63
1.08
Inferred
4.42
0.86
3.79
0.12
Total
39.62
0.94
37.42
1.20
Kami (oxide)
Measured
–
–
–
–
Indicated
14.60
0.61
8.87
0.29
Inferred
3.00
0.66
1.98
0.06
Total
17.60
0.62
10.85
0.35
Kami (transitional)
Measured
–
–
–
–
Indicated
2.59
0.97
2.53
0.08
Inferred
0.31
0.79
0.24
0.01
Total
2.90
0.96
2.77
0.09
Kosise
Measured
–
–
–
–
Indicated
4.55
0.70
3.19
0.10
Inferred
3.37
0.62
2.10
0.07
Total
7.93
0.67
5.30
0.17
Kounkoun
Measured
–
–
–
–
Indicated
–
–
–
–
Inferred
9.53
1.28
12.19
0.39
Total
9.53
1.28
12.19
0.39
Kozan North
Measured
–
–
–
–
Indicated
5.10
0.67
3.42
0.11
Inferred
0.57
0.69
0.39
0.01
94
SECTION 3 / CONTINENTAL AFRICA
Inclusive Mineral Resource continued
as at 31 December 2018
Category
Tonnes
million
Grade
g/t
Contained gold
tonnes
Moz
Total
5.67
0.67
3.81
0.12
Kozan South
Measured
–
–
–
–
Indicated
6.53
0.63
4.14
0.13
Inferred
0.34
0.92
0.31
0.01
Total
6.87
0.65
4.45
0.14
Seguélén (oxide)
Measured
–
–
–
–
Indicated
6.01
0.84
5.05
0.16
Inferred
2.09
0.76
1.59
0.05
Total
8.11
0.82
6.64
0.21
Seguélén (sulphide)
Measured
–
–
–
–
Indicated
1.56
1.08
1.70
0.05
Inferred
1.95
1.06
2.08
0.07
Total
3.52
1.07
3.77
0.12
Seguélén (transitional)
Measured
–
–
–
–
Indicated
0.72
0.95
0.68
0.02
Inferred
0.48
1.03
0.49
0.02
Total
1.19
0.98
1.17
0.04
Saraya (sulphide)
Measured
–
–
–
–
Indicated
3.43
1.93
6.61
0.21
Inferred
1.18
2.29
2.69
0.09
Total
4.61
2.02
9.31
0.30
Saraya (oxide)
Measured
–
–
–
–
Indicated
2.02
1.54
3.12
0.10
Inferred
0.50
1.65
0.82
0.03
Total
2.52
1.56
3.94
0.13
Saraya (transitional)
Measured
–
–
–
–
Indicated
0.24
2.07
0.49
0.02
Inferred
0.03
1.88
0.07
0.00
Total
0.27
2.05
0.56
0.02
Sintroko South
Measured
–
–
–
–
Indicated
2.70
1.19
3.21
0.10
Inferred
0.34
1.85
0.63
0.02
Total
3.04
1.26
3.84
0.12
Silakoro
Measured
–
–
–
–
Indicated
1.25
1.73
2.16
0.07
Inferred
0.03
1.03
0.03
0.00
Total
1.27
1.72
2.19
0.07
Sokunu
Measured
–
–
–
–
Indicated
7.78
0.75
5.86
0.19
Inferred
5.84
0.88
5.11
0.16
Total
13.62
0.81
10.98
0.35
Soloni
Measured
–
–
–
–
Indicated
4.32
0.56
2.44
0.08
Inferred
3.94
0.67
2.64
0.08
Total
8.26
0.62
5.08
0.16
Sorofe (fresh rock)
Measured
–
–
–
–
Indicated
2.06
1.19
2.45
0.08
Inferred
1.39
1.38
1.92
0.06
Total
3.46
1.26
4.37
0.14
Sorofe (oxide)
Measured
–
–
–
–
Indicated
4.14
1.15
4.78
0.15
95
SECTION 3 / CONTINENTAL AFRICA
SIGUIRI CONTINUED
Inclusive Mineral Resource continued
as at 31 December 2018
Category
Tonnes
million
Grade
g/t
Contained gold
tonnes
Moz
Inferred
3.26
1.20
3.92
0.13
Total
7.40
1.18
8.70
0.28
Sorofe (transitional)
Measured
–
–
–
–
Indicated
0.83
1.18
0.98
0.03
Inferred
1.53
1.66
2.54
0.08
Total
2.36
1.49
3.52
0.11
Stockpile (full grade ore)
Measured
6.74
0.90
6.06
0.19
Indicated
–
–
–
–
Inferred
–
–
–
–
Total
6.74
0.90
6.06
0.19
Stockpile (marginal ore)
Measured
13.62
0.50
6.83
0.22
Indicated
–
–
–
–
Inferred
–
–
–
–
Total
13.62
0.50
6.83
0.22
Stockpile (spent heap leach)
Measured
–
–
–
–
Indicated
31.95
0.54
17.29
0.56
Inferred
13.40
0.57
7.61
0.24
Total
45.35
0.55
24.90
0.80
Siguiri
Total
256.75
0.87
223.30
7.18
The Siguiri inclusive Mineral Resource is reported above the mineralised waste cut-off within economic pit shells, based on a gold
price of $1,400/oz and considering mining, processing and operational costs.
Estimation
Mineral Resource definition drilling is done with aircore drilling (AC), RC and DD. All available geological drill hole information is
validated for use in the Mineral Resource models and together with the local geology of the deposit, an understanding of grade
variability is used to categorise the drill hole information into appropriate estimation domains. Detailed statistical analyses are
conducted on each of these domains and this allows for the identification of high-grade outlier values.
The Mineral Resource model is estimated using ordinary kriging into a 3D block model. Geological interpretation is based on
geological drill hole data. The dimensions of these Mineral Resource blocks range from 10 x 10 x 2.5m to 50 x 25 x 6m block sizes,
guided by the shape of the deposit and the drilling density. The Mineral Resource is declared within an optimised Mineral Resource
pit shell using a gold price of $1,400/oz.
96
SECTION 3 / CONTINENTAL AFRICA
The grade tonnage curve does not include stockpiles.
Exclusive Mineral Resource
as at 31 December 2018
Category
Tonnes
million
Grade
g/t
Contained gold
tonnes
Moz
Siguiri
Measured
–
–
–
–
Indicated
97.67
0.87
85.03
2.73
Inferred
71.93
0.93
66.84
2.15
Total
169.60
0.90
151.87
4.88
The exclusive Mineral Resource at Siguiri includes:
•
Indicated Mineral Resource that is economic at the Mineral Resource gold price of US$1,400/oz but not at the Ore Reserve price
(this material forms approximately one third of the exclusive Mineral Resource)
•
Inferred Mineral Resource not included in the current pit designs (selected parts of these areas will be included in infill drilling
programmes during 2019 to meet LOM planning requirements)
•
Inferred Mineral Resource located within the Ore Reserve optimised pit shell (this material forms an insignificant proportion of the
exclusive Mineral Resource)
Grade tonnage curve
The Mineral Resource has remained relatively stable over the past year with only a 1% decrease on that reported in 2017. Depletion
at Seguélén, Silakoro, Kozan and stockpiles were offset by gains due to reduced cost which brought back Eureka North, exploration
infill drilling at Foulata, Saraya and Silakoro and metallurgical improvements due to the introduction of the CIL option for Foulata
and Saraya.
Year-on-year changes in Mineral Resource
97
SECTION 3 / CONTINENTAL AFRICA
SIGUIRI CONTINUED
As a low grade deposit, Siguiri is very sensitive to
gold price changes.
gold price changes.
Inclusive Mineral Resource sensitivity
98
SECTION 3 / CONTINENTAL AFRICA
ORE RESERVE
Ore Reserve
as at 31 December 2018
Category
Tonnes
million
Grade
g/t
Contained gold
tonnes
Moz
Bidini (fresh rock)
Proved
–
–
–
–
Probable
4.74
1.43
6.78
0.22
Total
4.74
1.43
6.78
0.22
Bidini (oxide)
Proved
–
–
–
–
Probable
1.92
0.84
1.61
0.05
Total
1.92
0.84
1.61
0.05
Bidini (transitional)
Proved
–
–
–
–
Probable
1.82
1.39
2.53
0.08
Total
1.82
1.39
2.53
0.08
Kami (fresh rock)
Proved
–
–
–
–
Probable
15.41
1.14
17.55
0.56
Total
15.41
1.14
17.55
0.56
Kami (oxide)
Proved
–
–
–
–
Probable
0.73
0.78
0.57
0.02
Total
0.73
0.78
0.57
0.02
Kami (transitional)
Proved
–
–
–
–
Probable
1.21
1.14
1.38
0.04
Total
1.21
1.14
1.38
0.04
Seguélén (sulphide)
Proved
–
–
–
–
Probable
0.50
1.11
0.56
0.02
Total
0.50
1.11
0.56
0.02
Seguélén (transitional)
Proved
–
–
–
–
Probable
0.00
0.76
0.00
0.00
Total
0.00
0.76
0.00
0.00
Silakoro
Proved
–
–
–
–
Probable
0.40
2.04
0.81
0.03
Total
0.40
2.04
0.81
0.03
Sorofe (fresh rock)
Proved
1.18
1.28
1.51
0.05
Probable
–
–
–
–
Total
1.18
1.28
1.51
0.05
Sorofe (oxide)
Proved
–
–
–
–
Probable
0.46
0.99
0.45
0.01
Total
0.46
0.99
0.45
0.01
Sorofe (transitional)
Proved
–
–
–
–
Probable
0.24
1.18
0.29
0.01
Total
0.24
1.18
0.29
0.01
Stockpile (full grade ore)
Proved
6.74
0.90
6.06
0.19
Probable
–
–
–
–
Total
6.74
0.90
6.06
0.19
Stockpile (marginal ore)
Proved
13.62
0.50
6.83
0.22
Probable
–
–
–
–
Total
13.62
0.50
6.83
0.22
Stockpile (spent heap leach)
Proved
–
–
–
–
Probable
31.95
0.54
17.29
0.56
Total
31.95
0.54
17.29
0.56
Siguiri
Total
80.94
0.79
64.22
2.06
99
SECTION 3 / CONTINENTAL AFRICA
SIGUIRI CONTINUED
Estimation
The Mineral Resource models for each pit are depleted to the current mined-out surface. Costs are assigned on a pit-by-pit basis,
reflecting the existing cost structure of the operation. The relevant dilution and ore-loss factors are applied and pit optimisation
is then performed. The relevant modifying factors such as metallurgical recoveries, geotechnical parameters, cut-off grades and
economics are applied to generate the mine designs that are used to estimate the final Ore Reserve.
Ore Reserve modifying factors
as at 31 December 2018
Gold
price
US$/oz
Cut-off
grade
g/t Au
Dilution
%
Dilution
g/t
RMF
% (based
on tonnes)
RMF
% (based
on g/t)
MRF
% (based
on tonnes)
MRF
% (based
on g/t
MCF
%
MetRF
%
Bidini (oxide)
1,100
0.6
28.1
0.2
100.0
100.0
80.6
88.0
100.0
93.0
Bidini (fresh rock)
1,100
0.7
17.6
0.1
100.0
100.0
85.5
91.3
100.0
93.0
Bidini (transitional)
1,100
0.7
18.1
0.1
100.0
100.0
83.1
89.6
100.0
93.0
Kami (oxide)
1,100
0.6
1.0
0.4
100.0
100.0
80.9
78.9
100.0
93.0
Kami (fresh rock)
1,100
0.7
1.5
0.5
100.0
100.0
99.0
99.3
100.0
93.0
Kami (transitional)
1,100
0.7
2.6
0.5
100.0
100.0
88.5
89.3
100.0
93.0
Seguélén (sulphide)
1,100
0.7
14.6
0.3
100.0
100.0
99.4
99.7
100.0
93.0
Seguélén (transitional)
1,100
0.7
14.6
0.3
100.0
100.0
92.8
95.8
100.0
93.0
Silakoro
1,100
0.6
2.4
0.4
100.0
100.0
76.5
74.3
100.0
91.0
Sorofe (oxide)
1,100
0.6
37.3
0.1
100.0
100.0
75.5
86.4
100.0
93.0
Sorofe (fresh rock)
1,100
0.7
12.6
0.1
100.0
100.0
86.7
92.1
100.0
93.0
Sorofe (transitional)
1,100
0.7
22.9
0.1
100.0
100.0
76.1
84.8
100.0
93.0
Stockpile (full grade ore)
1,100
–
–
–
100.0
100.0
100.0
100.0
100.0
91.0
Stockpile (marginal ore)
1,100
–
–
–
100.0
100.0
100.0
100.0
100.0
88.0
Stockpile (spent heap
leach)
1,100
–
–
–
100.0
100.0
100.0
100.0
100.0
90.0
The Mineral Resource models were modified to include the expected mining dilution and ore losses. These are built into the Mineral
Resource block model prior to pit optimisation. Additional modifying factors based on historical information were also applied prior
to estimation of Ore Reserve.
100
SECTION 3 / CONTINENTAL AFRICA
Positive model changes in the Ore Reserve from infill drilling in Silakoro and Seguélén, a decrease in costs mainly due to general and
administration, increased slope angle in Bidini and Tubani (Sorofe) and changes in stockpile inventories failed to cover the depletion.
Year-on-year changes in Ore Reserve
Inferred Mineral Resource in business plan
as at 31 December 2018
Tonnes
million
Grade
g/t
Contained gold
tonnes
Moz
Bidini (fresh rock)
0.81
1.28
1.04
0.03
Bidini (oxide)
0.83
0.95
0.79
0.03
Bidini (transitional)
0.20
1.26
0.25
0.01
Kami (fresh rock)
0.27
0.87
0.24
0.01
Kami (oxide)
0.00
0.45
0.00
0.00
Kami (transitional)
0.00
0.64
0.00
0.00
Seguélén (sulphide)
0.03
1.81
0.05
0.00
Silakoro
0.03
0.70
0.02
0.00
Sorofe (fresh rock)
0.37
1.38
0.51
0.02
Sorofe (oxide)
0.07
0.83
0.06
0.00
Sorofe (transitional)
0.01
0.83
0.01
0.00
Total
2.63
1.13
2.97
0.10
Ore Reserve does not include Inferred Mineral Resource, but within the pit design, Inferred Mineral Resource is included. For the
optimisation, the impact of excluding Inferred Mineral Resource is tested to determine if the pit sizes will still generate a positive cash
flow at $1,100/oz gold price.
The Inferred Mineral Resource within the Ore Reserve design is 4% of the total ore scheduled. The major contributor of Inferred
Mineral Resource material is Bidini. Inferred Mineral Resource exists as pockets located within the Bidini stage 1 design and will be
converted to Indicated and Measured once the access is provided (conversion costs are covered in the 2019/2020 exploration and
grade control budgets).
101
SECTION 3 / CONTINENTAL AFRICA
MALI
AngloGold Ashanti has interests
in three mines in the West African
country of Mali, with Morila being
operational, Sadiola being in a
limited operating phase and Yatela
undergoing closure. Sadiola and
Yatela are JV operations with
IAMGOLD and the state of Mali,
while Morila is a JV with Barrick and
the state of Mali. For Yatela, a sale
agreement has been entered into with
the state of Mali which is subject
to several conditions precedent
being fulfilled. Sadiola is currently
considering a major pushback to
access hard rock and Morila is a
mature operation focusing
on tailings reclamation and small
satellite deposits.
in three mines in the West African
country of Mali, with Morila being
operational, Sadiola being in a
limited operating phase and Yatela
undergoing closure. Sadiola and
Yatela are JV operations with
IAMGOLD and the state of Mali,
while Morila is a JV with Barrick and
the state of Mali. For Yatela, a sale
agreement has been entered into with
the state of Mali which is subject
to several conditions precedent
being fulfilled. Sadiola is currently
considering a major pushback to
access hard rock and Morila is a
mature operation focusing
on tailings reclamation and small
satellite deposits.
The Sadiola operation is managed
by AngloGold Ashanti while Barrick
manages Morila. There is no Mineral
Resource or Ore Reserve reported
for Yatela.
by AngloGold Ashanti while Barrick
manages Morila. There is no Mineral
Resource or Ore Reserve reported
for Yatela.
Mali – Sadiola
102
SECTION 3 / CONTINENTAL AFRICA
Inclusive Mineral Resource
as at 31 December 2018
Category
Tonnes
million
Grade
g/t
Contained gold
tonnes
Moz
Mali
Measured
4.86
0.54
2.62
0.08
Indicated
48.39
1.82
88.27
2.84
Inferred
7.23
1.68
12.19
0.39
Total
60.48
1.70
103.07
3.31
Exclusive Mineral Resource
as at 31 December 2018
Category
Tonnes
million
Grade
g/t
Contained gold
tonnes
Moz
Mali
Measured
–
–
–
–
Indicated
21.08
1.72
36.21
1.16
Inferred
7.23
1.68
12.19
0.39
Total
28.32
1.71
48.40
1.56
Ore Reserve
as at 31 December 2018
Category
Tonnes
million
Grade
g/t
Contained gold
tonnes
Moz
Mali
Proved
2.50
0.65
1.62
0.05
Probable
26.27
1.94
50.86
1.64
Total
28.78
1.82
52.48
1.69
LEGEND
1
Sadiola (41%)
2
Morila (40%)
3
Yatela
(1)
(40%)
0
400km
(1)
Yatela is currently in closure mode.
Operation
103
SECTION 3 / CONTINENTAL AFRICA
MORILA
INTRODUCTION
Property description
The mine is operated by Morila SA, a JV company incorporating Barrick (previously Randgold)
(40%), AngloGold Ashanti (40%) and the state of Mali (20%). Randgold took over the operation of
Morila mine from AngloGold Ashanti in February 2008. In 2009, Morila was converted to a stockpile
treatment operation. Closure of the operation was originally scheduled for 2013 but a pit pushback
and a tailings treatment project has extended its life to 2019.
Location
The Morila mine is situated some 280km south-east of Bamako, the capital city of Mali.
History
In 1996, Morila was discovered by Randgold. A PFS in 1998 supported the fast tracking of the
mine and, by August 1998, a bankable FS was underway. In 2000, a JV partner was sought and
AngloGold purchased 40% of the mine and became the operator of the mine. In February 2001, the
Malian president officially opened the mine.
During 2003, a capital expansion programme was completed and increased the production level to
350,000t per month by year-end. In 2008, AngloGold Ashanti considered Morila to be non-strategic
and Randgold took over the operational responsibility for Morila.
In 2009 Morila started its transition to a stockpile and tailings retreatment operation.
Legal aspects and tenure
Morila’s exploitation permit PE 99/15 (Decree No 99-217/PM-RM) covers 199.8km2 and was
issued on 4 August 1999 for 30 years. An agreement between Birimian Gold Mali SARL (Birimian)
and Morila was signed on 24 October 2016 for the Morila team to undertake a six-month feasibility
study on the Viper target. The agreement to exercise the option from Birimian was taken after six
months on 24 April 2017. The permit was transferred to Morila on 17 May 2018 with the Decret No
99-361/PM-RM. Birimian retain a 22% Royalty and 11% option on the Viper deposit.
Mining method
Production of the Viper satellite pit is via conventional open pit mining methods. All other production
is from retreatment of tailings and stockpiles.
Operational infrastructure
All operational infrastructures are in place to support a mining operation including a processing plant,
power generation, village and TSF.
Mineral processing
Satellite pit ore together with tailing materials are being processed. The metallurgical plant utilises
a conventional CIL process with an upfront gravity section to extract the free gold and has annual
throughput capacity of 4.3Mt.
Risks
No material risks have been identified.
104
SECTION 3 / CONTINENTAL AFRICA
Licences
Mining
Mine infrastructure
Pits
Plant
ROM pad
TSF
Waste dumps
Settlements
Villages
Roads
Main
Secondary
Airfield
Plant centroid co-ordinates
06°50’23”W, 11°40’43”N
1.5
0
1.5
3km
Planned
Waste dump and pit
Waste dump and pit
Map showing Morila Mine infrastructure and licences
105
SECTION 3 / CONTINENTAL AFRICA
MORILA CONTINUED
Competent Persons
Responsibility
Competent Person
Professional organisation
Membership
number
Relevant
experience
Qualification
Mineral Resource and
Ore Reserve
Simon Bottoms*
Geological Society of
London (FGS CGeol)
1 023 769
9 years
MGeol
* Employed by Barrick as SVP, Africa and Middle East Mineral Resource Manager, 3rd Floor, Unity Chambers, 28 Halkett Street, St. Helier, Jersey,
Channel Islands
GEOLOGY
The Morila deposit occurs within a sequence of amphibolite facies Birimian metasediments. The economic mineralisation is located
in these metasediments within a broad north-northwest trending corridor of shearing. This shear zone has near-vertical and at-
lying components and is interpreted as being a second-order shear off the main Banafin shear, approximately 25km to the east. The
Doubalakoro granite pluton borders the metasediments to the west and the Massigui granites lie to the east. Gold mineralisation is
associated with silica-feldspar alteration and the sulphide minerals arsenopyrite, pyrrhotite and pyrite (with minor chalcopyrite).
EXPLORATION
Recent exploration at Morila has been limited to reviews of potential targets, including the Samacline area and drilling at the satellite
pits in support of the production from Viper and Ntiola.
PROJECTS
Birimian option agreement
In 2016, Morila signed an option agreement with Birimian, which provides Morila access to Birimians’ Ntiola and Viper projects
which are adjacent to the existing Morila permit.
MINERAL RESOURCE
Details of average drill hole spacing and type in relation to Mineral Resource classification
Category
Spacing m (-x-)
Type of drilling
Comments
Diamond
RC
Blasthole
Channel
Other
Measured
10 x 5, 50 x 100
–
√
√
√
√
–
–
Auger drilling
Indicated
10 x 20
–
√
–
–
√
–
–
Inferred
20 x 40
–
–
–
–
Grade/ore control
10 x 5
–
–
–
–
–
Inclusive Mineral Resource
as at 31 December 2018
Category
Tonnes
million
Grade
g/t
Contained gold
tonnes
Moz
Satellite pit
Measured
–
–
–
–
Indicated
0.16
1.44
0.22
0.01
Inferred
–
–
–
–
Total
0.16
1.44
0.22
0.01
Stockpile (full grade ore)
Measured
0.03
1.47
0.05
0.00
Indicated
–
–
–
–
Inferred
–
–
–
–
Total
0.03
1.47
0.05
0.00
TSFs
Measured
4.78
0.52
2.49
0.08
Indicated
–
–
–
–
Inferred
–
–
–
–
Total
4.78
0.52
2.49
0.08
Morila
Total
4.97
0.56
2.76
0.09
Estimation
106
SECTION 3 / CONTINENTAL AFRICA
The grade tonnage curve does not include stockpiles.
Morila is not sensitive to an increase in gold price
and insensitive on the downside as it is a mature
operation at the end of its life with very little
additional opportunity.
and insensitive on the downside as it is a mature
operation at the end of its life with very little
additional opportunity.
Depletions have been partially offset by the addition of Viper and Ntiola open pits from exploration.
Year-on-year changes in Mineral Resource
Inclusive Mineral Resource sensitivity
Grade tonnage curve
The Mineral Resource consists of material from TSF and Domba pit as marginal and mineralised waste stockpiles are depleted. The
TSF forms the bulk of the Mineral Resource and was drilled on a spacing of 50 x 50m and estimated using ordinary kriging methods
into a 50 x 50m block size.
107
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MORILA CONTINUED
ORE RESERVE
Ore Reserve
as at 31 December 2018
Category
Tonnes
million
Grade
g/t
Contained gold
tonnes
Moz
Satellite pit
Proved
–
–
–
–
Probable
0.17
1.31
0.22
0.01
Total
0.17
1.31
0.22
0.01
Stockpile (full grade ore)
Proved
0.03
1.47
0.05
0.00
Probable
–
–
–
–
Total
0.03
1.47
0.05
0.00
TSF
Proved
2.42
0.62
1.50
0.05
Probable
–
–
–
–
Total
2.42
0.62
1.50
0.05
Morila
Total
2.62
0.67
1.76
0.06
Estimation
The Mineral Resource models are used as the basis for the Ore Reserve. All appropriate costs, metallurgical recovery factors and
geotechnical parameters are applied to generate the mine designs that are used to estimate the final Ore Reserve.
Ore Reserve modifying factors
as at 31 December 2018
Gold
price
US$/oz
Cut-off
grade
g/t Au
Dilution
%
MRF
% (based
on tonnes)
MCF
%
MetRF
%
Satellite pit
1,000
0.79
10.0
97.0
98.0
91.0
TSF
1,000
0.49
5.0
–
100.0
57.0
$1,000/oz Ore Reserve price used by Barrick (operating partner)
Inferred Mineral Resource in business plan
There is no Inferred Mineral Resource included in the business plan.
Depletions were partially offset by the addition of Viper and Ntiola open pits from exploration.
Year-on-year changes in Ore Reserve
108
SECTION 3 / CONTINENTAL AFRICA
SADIOLA
INTRODUCTION
Property description
The Sadiola gold deposit is mined by the Société d’Exploration des Mines d’Or de Sadiola S.A.
(SEMOS) that is a JV agreement between AngloGold Ashanti (41%), IAMGOLD Corporation (41%)
and the state of Mali (18%).
Location
Sadiola is situated in western Mali, 77km to the south of the regional capital of Kayes and about
440km north-west of the capital city of Bamako. The property lies within the Galam Bambouk gold
area, which straddles the Mali-Senegal border close to the border with Guinea.
History
Sadiola has a history of alluvial gold working dating back to the 11th century. In 1991/1992
IAMGOLD acquired the rights to the concession and explored the area, and in 1993 Anglo American
entered into an earn-in option to the property. In 1994, a FS was completed on the property and
accepted by the Mali government.
Construction started in 1995 and on 20 December 1996 the first gold was poured.
In November 2009, IAMGOLD and AngloGold Ashanti announced that they were acquiring the
International Finance Corporation’s 6% interest for a total of $14.5 million.
A FS, Sadiola Sulphide Project (SSP), looking at mining and processing the sulphide ore was
completed in 2016. However, a decision to proceed remains on hold while awaiting the conclusion
of negotiations with the government. The oxide mining activities were completed in early 2018. While
awaiting the decision, the operation continues to process oxide stockpiled material.
Legal aspects and tenure
SEMOS is bound by the original prospecting and exploitation agreement (including its subsequent
legal modifications) entered into on 5 April 1990 between AGEM Limited. (AGEM) and the state
of Mali, valid for the original mineral commodities until 5 April 2020. The identity number of the
current exploitation area, DECRET No 00-080/PM-RM DU 06 MARS 2000 is a modification of all
previous exploitation areas. Sadiola is operated under the license DECRET No 00-080/PM-RM DU
06 MARS 2000 valid from 1 August 1994 to 1 August 2024 covering a total area of 303km2. The
SSP project will extend operations beyond 2024. Dialogue with the government of Mali has been
ongoing throughout the project study phase and, as such, there are no foreseeable reasons why the
amended ESIA and associated approvals should not be approved.
Mining method
Open pit mining operations ceased at Sadiola in 2018. The operation is currently based around
stockpile re-claim with ore feed scheduled until Q3 of 2019.
The SSP is currently in care and maintenance. The ore re-claim is undertaken using a mining eet
consisting of a loader and rear dump trucks. The planned mining method for the SSP is conventional
open pit mining, using a combination of hydraulic face shovels and rear dump trucks working on
10m benches.
Operational infrastructure
Sadiola includes a main pit and several smaller satellite pits, a processing plant, a TSF and other
infrastructure such as a mine village, water supply system, roads, airstrip and communications systems.
Since the beginning of the operation mining activities have been outsourced. All mining occurs within
the mining licence boundaries.
Mineral processing
Ore is treated in a 4.9Mtpa CIP processing plant. The plant was originally designed to treat only
soft oxide ore, but has been progressively adapted to include a blend of hard oxides as well as
batch feeding of a sulphide ore blend. Any hard material making up the blend currently undergoes
preconditioning through separate primary crushers.
The SSP aims to mine the underlying sulphide material in the Sadiola main pit and modify the existing
oxide plant to process the sulphide ore. The modified plant will treat both sulphide stockpiles and the
ROM sulphide material. This project will extend the life of Sadiola and leverage any further sulphide
exploration successes in the region.
109
SECTION 3 / CONTINENTAL AFRICA
Risks
The oxide ore from pits was finished in March 2018. Since then, only oxide stockpiles are available
and can feed the processing plant until Q3 2019.
The SSP project has been re-evaluated based on the current economic climate. As part of the
revision, an amended ESIA was completed in 2017 and approved by the government of Mali.
With the current LOM schedule, the oxide ore from pits was finished in 2018. Since then, low grade
stockpiles are being fed to the process plant, and will form the feed supply until Q3 of 2019.
The project is paused pending favourable conclusion of discussions with the government of Mali on
fiscal agreements.
SADIOLA CONTINUED
Competent Persons
Responsibility
Competent Person
Professional
organisation
Membership
number
Relevant
experience
Qualification
Mineral Resource
Geoffrey Gushee
FAusIMM
207 957
30 years
BA (Geology), GDE (Mining
Engineering), MEng (Mineral
Resource Management), MDP
Ore Reserve
Andrew Bridges
MAusIMM
300 976
20 years
BSc Hons (Mining Engineering)
GEOLOGY
The Sadiola gold deposits are located within the Malian portion of the Kenieba-Kedougou Inlier, a major early Paleoproterozoic-
Birimian window along the northeast margin of the Kenema-Man shield. The deposits are in the north of the inlier and positioned in
the Ko Formation, just east of the Senegalo-Malian Shear Zone terrane boundary. Greenschist facies regional metamorphism with
amphibolite facies metamorphism is observed in the contact aureoles around major intrusions.
Deposit type
The Sadiola deposit is considered a mesothermal shear-hosted gold deposit and can be correlated with an Ashanti-type orogenic
gold model.
Mineralisation style
The Sadiola gold system displays the Sadiola Hill-style Au-As-Sb mineralisation. Within the Sadiola main pit, the bulk of the ore is
hosted within the brittle-ductile Sadiola Fracture Zone (SFZ) and impure footwall carbonates. Mineralisation also occurs along the
array of NNE-trending shears although gold grade decreases with increasing distance from the SFZ.
Mineralisation is shear-hosted and associated with a polyphase hydrothermal alteration history comprising an early calc-silicate
phase followed by a potassic alteration stage. The metal associations of the ore typically comprise As-Au-Sb and minor to trace
amounts of Cu-W-Mo-Ag-Bi-Zn-Pb-Te-Fe-bearing mineral species.
Structural controls on primary mineralisation in the FE satellite pits are similar to that of Sadiola but later karstification and protracted
weathering resulted in the formation of a gold residuum.
Lithostratigraphic contacts also appear to have been an efficient interface for channeling fluids.
Oxide mineralisation
The geometry of the extensive, soft, oxide deposit and its supergene enrichment of gold relates almost exclusively to the weathering
history of the primary mineralisation. Intense tropical weathering has produced deep troughs of white to grey, decarbonated, kaolin-
rich saprolite, locally abundant nontronite and relative gold enrichment. Penetration of groundwater has caused oxidation of the
primary sulphides and the formation of acidic groundwaters, further promoting deeper argillisation of the bedrock.
Sulphide mineralisation
Drilling of the (unweathered) primary mineralisation has allowed detailed investigation of major and minor hydrothermal alteration
processes that were active during the formation of the deposit. Primary gold is fine grained, dominantly less than 15 microns,
with rare grains approaching 50 microns. Visible gold is rare. Gold mineralisation is associated with both arsenic and antimony
dominated sulphide assemblages of arsenopyrite, pyrrhotite, pyrite, stibnite and gudmuntite as well as potassic, calc-silicate,
propylitic alteration and silicification.
110
SECTION 3 / CONTINENTAL AFRICA
Licences
Mining
Mine Infrastructure
Pits
Plant
ROM pad
TSF
Return water dam
Raw water dam
Waste dumps
Settlements
Towns
Mine village
Villages
Roads
Main
Secondary
Airfield
0
2
4
6km
Plant centroid co-ordinates
11°40’09”W, 13°53’27”N
Map showing Sadiola Mine infrastructure and licences
111
SECTION 3 / CONTINENTAL AFRICA
SADIOLA CONTINUED
W
-100m
-
200m
-300m
-400m
100m
Ductile shear zone with mixed protolith
Brittle shear zone – carbonate breccia
Quartz-feldspar-phyric felsic metadyke
Metadiorite
Hangingwall metagreywacke
Footwall impure metalimestone
Orebody – Sadiola fracture zone (SFZ)
Section definition boundary
Elevation
E
Legend
Mineralisation characteristics
The gold mineralisation in the Sadiola main pit is related to the interaction of the north-striking SFZ and a north-northeast-striking
fault array. The SFZ follows the competency contrast between the brittle hangingwall greywacke and the ductile footwall marbles
and is mineralised over a drilled strike length of approximately 2,500m. The stratigraphy is intruded by discontinuous diorite and
quartz-feldspar porphyry dykes. Mineralisation occurs in all four rock types although most of the mineralisation is hosted in the
footwall carbonates adjacent to the SFZ. The deposit has been intensely weathered to a maximum depth of 200m.
At the FE pits, located about 7km to the southeast of the Sadiola main pit, mineralisation is hosted in marbles adjacent to the upper
contact with carbon-rich pelites. Gold is associated with north-northeast to north-east striking faults and lens-shaped breccia zones
that are broadly parallel to the north-west-trending stratigraphy. The FE4 deposit is located in an interbedded sandstone and pelite
sequence with mineralisation predominantly hosted in breccia along a north-east striking regional shear and several subsidiary
north-northeast-trending faults.
At Tambali, located 2km to the south of the Sadiola main pit, the mineralisation is associated with two sets of structures, orientated
north-northeasterly (dipping steeply south-east) and north-westerly (dipping south-west). These structures are often related to thin
tourmaline-quartz-rich shears/veins or zones of (mostly north-northeast trending) quartz-feldspar porphyry intrusions that have
undergone later shearing. A north-west trending graphite-rich brecciated boundary between southwesterly-dipping sandstones (in
the east) and metapelites (in the west) is also evident. Bedding parallel shearing is also indicated in some areas, possibly accounting
for some of the westerly-dipping mineralised structures. Tambali mineralisation is similar in style to the Sadiola main pit and it is
subjected to similar structural controls.
W-E Geological cross-section through the Sadiola pit, elevation in metres relative to average mean sea level
112
SECTION 3 / CONTINENTAL AFRICA
EXPLORATION
Exploration activities wound down in early 2018 as the mine was heading into restricted operations, pending the outcome of the
SSP project.
PROJECTS
The SSP remains the only major AngloGold Ashanti project in Mali and is the focus for extension of the LOM. The project has been
re-evaluated and optimised in light of the current economic and political climate. The project consists of a new pushback in the
Sadiola main pit in order to mine the underlying sulphide ore, and an expansion and upgrade of the existing processing plant to be
able to treat the sulphide ore. The revised project extends operations beyond 2024. As part of the revision, an amended ESIA was
completed in 2017 and approved by the government of Mali. Dialogue with the government of Mali has been ongoing throughout
the project study phase. The project is paused pending favourable conclusion of discussions with the government of Mali on scal
agreements.
MINERAL RESOURCE
Details of average drill hole spacing and type in relation to Mineral Resource classification
Category
Spacing m (-x-)
Type of drilling
Diamond
RC
Blasthole
Channel
Other
Measured
6.25 x 12.5, 25 x 25
√
√
√
√
–
–
–
Indicated
25 x 25, 50 x 25
√
√
√
√
–
–
–
Inferred
50 x 50
–
–
–
Grade/ore control
5 x 10, 6.25 x 12.5
–
–
–
113
SECTION 3 / CONTINENTAL AFRICA
SADIOLA CONTINUED
Inclusive Mineral Resource
as at 31 December 2018
Category
Tonnes
million
Grade
g/t
Contained gold
tonnes
Moz
FE2
Measured
–
–
–
–
Indicated
0.14
1.48
0.20
0.01
Inferred
0.00
1.30
0.00
0.00
Total
0.14
1.48
0.20
0.01
FE3
Measured
–
–
–
–
Indicated
1.02
1.88
1.93
0.06
Inferred
0.03
2.13
0.07
0.00
Total
1.06
1.89
2.00
0.06
FE4
Measured
–
–
–
–
Indicated
0.03
2.25
0.06
0.00
Inferred
0.01
2.84
0.03
0.00
Total
0.04
2.39
0.09
0.00
FN
Measured
–
–
–
–
Indicated
2.44
1.35
3.29
0.11
Inferred
0.30
1.19
0.36
0.01
Total
2.74
1.33
3.65
0.12
Tabakoto (Sekokoto)
Measured
–
–
–
–
Indicated
0.33
1.23
0.41
0.01
Inferred
0.05
1.12
0.05
0.00
Total
0.38
1.22
0.46
0.01
Tambali
Measured
–
–
–
–
Indicated
1.70
1.04
1.77
0.06
Inferred
0.50
1.19
0.59
0.02
Total
2.20
1.08
2.36
0.08
SSP (oxide)
Measured
–
–
–
–
Indicated
1.71
1.30
2.24
0.07
Inferred
0.19
1.05
0.20
0.01
Total
1.91
1.28
2.44
0.08
SSP (transitional)
Measured
–
–
–
–
Indicated
1.18
1.89
2.22
0.07
Inferred
0.14
1.57
0.22
0.01
Total
1.32
1.85
2.44
0.08
SSP (sulphide)
Measured
–
–
–
–
Indicated
36.75
1.94
71.44
2.30
Inferred
6.02
1.77
10.67
0.34
Total
42.77
1.92
82.11
2.64
Total stockpiles
Measured
0.05
1.66
0.08
0.00
Indicated
2.93
1.53
4.48
0.14
Inferred
–
–
–
–
Total
2.98
1.53
4.56
0.15
Sadiola
Total
55.52
1.81
100.31
3.23
114
SECTION 3 / CONTINENTAL AFRICA
Estimation
The Mineral Resource is taken as the material that falls within the $1,400/oz economic pit shell optimised for each individual
deposit. A 3D surface is generated to create the outline of the geological model within which grades are estimated. Block sizes are
between 25 x 25 x 10m and 30 x 30 x 10m and, where appropriate, selective sub-celling is used for definition on the geological and
mineralisation boundaries. All the deposits are estimated by ordinary kriging. Where deemed appropriate, a geostatistical technique
called uniform conditioning (UC) or localised uniform conditioning (LUC) is used to estimate the proportion of material that occurs
above the cut-off, hence forming a recoverable Mineral Resource model at a specific SMU.
Grade tonnage curve
The grade tonnage curve does not include stockpiles.
Exclusive Mineral Resource
as at 31 December 2018
Category
Tonnes
million
Grade
g/t
Contained gold
tonnes
Moz
Sadiola
Measured
–
–
–
–
Indicated
21.08
1.72
36.21
1.16
Inferred
7.23
1.68
12.19
0.39
Total
28.32
1.71
48.40
1.56
The exclusive Mineral Resource is the part of the Mineral Resource that was not converted to Ore Reserve. It is defined as the
Mineral Resource that is outside the current Ore Reserve designs, but inside the Mineral Resource shells and includes the Inferred
Mineral Resource within the Ore Reserve design.
The exclusive Mineral Resource gives an indication of the future potential of the deposit. This material could be converted to Ore
Reserve with an increase in the gold price and favourable costs. The Inferred Mineral Resource portion of the Mineral Resource
within the Ore Reserve pit design will be converted to the Ore Reserve through grade control drilling.
115
SECTION 3 / CONTINENTAL AFRICA
SADIOLA CONTINUED
The Mineral Resource models and inputs used to tabulate the Mineral Resource were the same as the previous year. The main
change is due to depletion.
Year-on-year changes in Mineral Resource
Sadiola is very sensitive to a drop in gold price due
to the low grade nature of the stockpiles.
to the low grade nature of the stockpiles.
Inclusive Mineral Resource sensitivity
116
SECTION 3 / CONTINENTAL AFRICA
ORE RESERVE
Ore Reserve
as at 31 December 2018
Category
Tonnes
million
Grade
g/t
Contained gold
tonnes
Moz
FN
Proved
–
–
–
–
Probable
0.78
1.48
1.15
0.04
Total
0.78
1.48
1.15
0.04
SSP (oxide)
Proved
–
–
–
–
Probable
0.66
1.56
1.03
0.03
Total
0.66
1.56
1.03
0.03
SSP (transitional)
Proved
–
–
–
–
Probable
0.70
2.10
1.47
0.05
Total
0.70
2.10
1.47
0.05
SSP (sulphide)
Proved
–
–
–
–
Probable
21.03
2.02
42.51
1.37
Total
21.03
2.02
42.51
1.37
Total stockpiles
Proved
0.05
1.66
0.08
0.00
Probable
2.93
1.53
4.48
0.14
Total
2.98
1.53
4.56
0.15
Sadiola
Total
26.15
1.94
50.72
1.63
Estimation
The Mineral Resource models are used as the basis for the Ore Reserve. Optimisations are run on the Measured, Indicated and
Inferred Mineral Resource. All appropriate costs, metallurgical recovery factors and geotechnical parameters are applied to generate
the mine designs that are used to estimate the final Ore Reserve.
Ore Reserve modifying factors
as at 31 December 2018
Gold
price
US$/oz
Cut-off
grade
g/t Au
Dilution
%
RMF
% (based
on g/t)
MCF
%
MetRF
%
FN
1,200
0.77
17.6
85.0
100.0
76.0
SSP (oxide)
1,200
0.51
0.0
0.0
100.0
94.0
SSP (transitional)
1,200
0.78
0.0
0.0
100.0
75.0
SSP (sulphide)
1,200
0.77
0.0
0.0
100.0
76.0
Total stockpiles
1,200
0.68
–
–
100.0
78.0
MetRF varies according to ore type (laterite, saprolite, siliceous oxide, saprolitic sulphide, hard sulphide, intermediate oxide,
intermediate sulphide, transitional and graphitic). A $1,200/oz Ore Reserve price is used for the SSP project and short term oxide
pits.
The modifying factors applied to the Ore Reserve for Sadiola are ore loss and dilution. For the satellite pits, due to the nature of the
mineralisation, the ore loss and dilution are different from the SSP main pit.
The SSP main pit utilises ore loss incorporated into the modelling process. The other satellite pits have variable ore loss and dilution
applied dependent on mining method. The satellite pits that are to be mined as part of the SSP have 15% ore loss and 17.6%
dilution applied. The latter is to allow for mining by a face shovel rather than an excavator.
Inferred Mineral Resource in business plan
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SADIOLA CONTINUED
118
SECTION 3 / CONTINENTAL AFRICA
as at 31 December 2018
Tonnes
million
Grade
g/t
Contained gold
tonnes
Moz
FN
0.02
1.24
0.03
0.00
SSP (oxide)
0.04
1.16
0.05
0.00
SSP (transitional)
0.05
1.12
0.06
0.00
SSP (sulphide)
0.52
1.16
0.60
0.02
Total
0.64
1.16
0.74
0.02
Inferred Mineral Resource has been included in the business plan as incidental material when the pit is mined. Several of the satellite
pits that are included in the SSP contain Inferred Mineral Resource with the overall Inferred Mineral Resource included in the total
business plan totalling approximately 2%.
Mainly due to depletion and the exclusion of Tambali and FE3 pits.
Year-on-year changes in Ore Reserve
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TANZANIA
Geita is AngloGold Ashanti’s only
operation in Tanzania and one of
the largest open pit gold mines
in Africa. Prior to April 2004,
Geita was managed under a JV
agreement between Ashanti and
AngloGold. Since the merger, Geita
is a wholly owned subsidiary of
AngloGold Ashanti.
In 2016, underground mining
successfully started at Star
and Comet to provide ore to the
processing plant. Underground ore
is now a significant part of the
feed to the plant with underground
operations also having commenced
at Nyankanga.
Tanzania – Geita
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Exclusive Mineral Resource
as at 31 December 2018
Category
Tonnes
million
Grade
g/t
Contained gold
tonnes
Moz
Tanzania
Total
41.37
3.70
153.19
4.93
Ore Reserve
as at 31 December 2018
Category
Tonnes
million
Grade
g/t
Contained gold
tonnes
Moz
Tanzania
Total
9.47
4.38
41.49
1.33
LEGEND
1
Geita
0
200km
Operation
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GEITA
INTRODUCTION
Property description
Geita is wholly owned by AngloGold Ashanti and currently sources ore from the Nyankanga open
pit and three underground sections (Star and Comet Cut 2, Star and Comet Cut 3 and Nyankanga
Block 5). Underground mining commenced at Star and Comet in 2016 and at Nyankanga in 2017.
Location
Geita Gold Mine (GGM) is located approximately 910km from the Tanzanian capital city of Dar es
Salaam. It falls within the Lake Zone of northern-western Tanzania, approximately 120km west
of Mwanza and 4km away from the town of Geita. The mining lease area falls within the Archean
Sukumaland Greenstone Belt of the Lake Victoria goldfields.
History
In 1936, the Geita deposits were first discovered and by 1966, three mines had produced almost 1Moz.
Ashanti acquired the project through acquisition of Cluff Resources in 1996 and in early December
2000, Ashanti reached an agreement to sell AngloGold a 50% interest in Geita for $324 million.
AngloGold added its neighbouring Nyamulilima Hill deposits into the JV company. In 2004, the
merger of AngloGold and Ashanti resulted in the operation being run by AngloGold Ashanti.
The decision was taken to go underground at Star and Comet in 2015 and the underground
development started in 2016. In 2017 the Nyankanga underground operation was started.
Legal aspects and tenure
The special mining licence (SML45/99) covers approximately 196.17km2 and expires on
26 August 2024. There are a further 120km2 of prospecting licences in the immediate vicinity to the
SML. However, these do not contain any Ore Reserve.
Mining method
Mining at Geita is by both open pit and underground methods. The open pit mining is currently
undertaken by conventional truck-and-shovel open pit mining method on one active pit (Nyankanga).
The open pit mining is conducted using Geita owned, operated and maintained eet. A contractor
provides drilling and blasting services. Underground mining commenced at Star and Comet in 2016
and subsequently at Nyankanga in 2017 using the services of an underground mining contractor.
Ore is hauled from the Star and Comet operation to the central ROM pad by the Geita surface
mining eet.
Operational infrastructure
Geita has an established 5.2Mtpa CIL processing plant capable of processing hard ore. It also has
an established TSF with sufficient area to construct wall raises every three years to accommodate
planned future production. A full workshop facility is in place to support the maintenance of heavy
mining equipment and all light support equipment. Contractor infrastructure supported on the
mine site includes workshops for the production and exploration drilling contractor, workshops for
the underground mining contractor, as well as a plant for the explosives supplier. Geita has further
support infrastructure in place including a mine village, medical clinic, mine store, administration
buildings and an airstrip.
Mineral processing
Geita’s ore processing method is via conventional CIL process. The CIL plant has a throughput
capacity of 5.2Mtpa. The circuit contains a primary gyratory crusher, secondary and tertiary crushers,
a semi-autogenous mill, ball mill and 12 leach tanks. This is coupled with a gravity circuit through
two knelson concentrators. In planning the plant feed blend material hardness, grade and sulphide
content are considered in order to optimise throughput and recovery.
Risks
There are regular artisanal and small scale miners activities and illegal intrusions into the mine, but
there is a holistic mitigation plan in process to manage this.
The primary risk remains the changing Ore Reserve profile from open pit to underground. The
mitigating actions put in place focus on optimising the exploration and project plans to convert
both surface and underground Mineral Resource to Ore Reserve. The other risks include, reduced
underground production efficiencies when transitioning to owner mining in selected areas, ball mill
and crusher plant integrity, Mineral Resource to Ore Reserve conversion, open pit and underground
blasting interaction for Nyankanga Cut 8 and Nyankanga Block 3 underground and the aging eet for
open pit.
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Competent Persons
Map showing Geita Mine infrastructure and licences
0
1.5
3
4.5km
Plant centroid co-ordinates
32°11’12”W, 2°51’53”N
Licences
Mining
Exploration
Underground access
Active
Planned
Planned
Mine infrastructure
Pits
Plant
ROM pad
Stockpiles
TSF
Waste dumps
Raw water dam
Deposit
Plant
ROM pad
Stockpiles
TSF
Waste dumps
Raw water dam
Deposit
Settlements
Towns
Villages
Roads
Main
Secondary
Secondary
Airfield
GEOLOGY
Deposit type
The Geita Greenstone Belt (GGB) hosts several world-class shear-hosted Archean lode gold deposits and forms the northern
portion of the regional Sukumaland Greenstone Belt, itself one of several belts that comprise the Lake Victoria goldfields. Other gold
mines hosted in the Lake Victoria Goldfields include Golden Pride, Bulyanhulu, Tulawaka, Buzwagi and North Mara.
The east-west oriented GGB is 60km in length, up to 15km wide. The Geita terrain is comprised of upper- to mid-Nyanzian
greenschist facies units, made up of clastic sediments, black shales, banded iron formation (BIF), volcanoclastics and metabasalts.
These have been intruded by a variety of felsic to mafic intrusive bodies, dykes and sills. Gabbro dykes accommodated by regional
north-northeasterly structures are also prominent geological features in the area.
North-west trending deformation corridors divide the GGB into three distinct sub-terrains, namely the Nyamulilima Terrain in the
west (hosting the Star and Comet, Ridge 8 and Roberts deposits), the Central Terrain in the central part (hosting the Nyankanga,
Geita Hill, Lone Cone and Chipaka deposits) and the Kukuluma Terrain to the north-east (hosting the Matandani, Kukuluma and
Area 3 West deposits).
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GEITA CONTINUED
Mineralisation style
Geita’s gold mineralisation is preferentially hosted in BIF, cherts and ironstones that have been affected by both ductile and dominant
brittle deformation associated with shear zones. The shears preferentially exploit fold axial planes as well as the contacts between
the supracrustal and intrusive rocks.
The GGB has been through a protracted history of deformation, which resulted in a large-scale synformal configuration in the
Central Terrain, with west-northwest trending limbs connected by a north-east trending hinge zone. The deposits of the Central
Terrain are mainly located within the relatively low-strain hinge zone.
The Nyankanga deposit is hosted in a BIF-dominated supracrustal package that is extensively intruded by, and locally form a roof-
pendant within the dioritic Nyankanga Intrusive Complex. At Geita Hill, dioritic rocks are present as sills and dykes intruded into a
supracrustal sequence that has been subject to extensive polyphase folding.
To the west, the Nyamulilima Terrain comprises a semi-circular structure surrounding intrusive centers, which internally
encompasses structural systems of variable scale that locally control gold mineralisation. At Star and Comet, a folded sedimentary
package of BIF intercalated with clastic and tuffaceous metasediments is intruded by a tonalitic complex.
The Kukuluma Terrain trends west-northwesterly, with sub-vertical limbs being dominant over compressed, multiphase folded zones.
The three major deposits in the area (Kukuluma, Matandani and Area 3) are located along a 5km long east-southeast mineralisation
trend. The geology of the deposits is dominated by volcano-sedimentary rocks that are polydeformed and intruded by syn- to late-
folding diorite bodies. Host rocks for mineralisation are fine-grained iron-rich clastic sediments, cherts, BIF and tuffaceous rocks,
with local intercalated carbonaceous shales.
Mineralisation characteristics
Gold mineralisation at Nyankanga occurs within a northeast trending and northwest dipping anastomosing shear system, typically
along the lowermost shears, with higher grade mineralisation mainly proximal to the basal contact of BIF packages. Mineralisation
is associated with chlorite-carbonate-silica alteration and pyrite-dominant sulphide in the damage zones surrounding the shear
surfaces as veins, veinlets, local breccias and sulphide replacement of magnetite layers. At Geita Hill, mineralisation at the deposit
scale is controlled by a narrow northeast trending and northwest dipping shear zone that exploits the axial surfaces of F3 folds.
The bulk of the ore is also carried by damage zones adjacent to the main shear.
At Star and Comet, a major mineralised shear zone runs north-northwest to south-southeast through the deposit where it is
localised along the contact of BIF and tonalite. An envelope of mostly brittle deformation up to 10m thick (which affects both
lithologies) occurs either side of the shear zone and controls distribution of mineralisation. Most of the gold mineralisation is hosted
in pyrrhotite patches associated with strong silicification together with carbonate alteration.
Within the Kukuluma Terrain, steeply dipping ductile/brittle gold-fertile shear zones are developed along, or close to, the edges of
an elongate diorite body, hosted in iron-rich host rocks and locally exploiting axial surfaces of tight folds. Gold mineralisation in the
Kukuluma terrain is strongly associated with pyrrhotite, pyrite and arsenopyrite concentrations, accompanied by strong carbonate
and silica alteration of host rocks. Gold is present in gold minerals and sulphides, dominantly in arsenopyrite.
Geita Hill, Lone Cone, Nyankanga Long Section: potential down-plunge ore shoots (view looking SE)
Indicated and Inferred Mineral Resource @ Au>2g/t
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SECTION 3 / CONTINENTAL AFRICA
EXPLORATION
A total of 68,313m surface and underground exploration drilling was completed during the year consisting of 64,050m of DD and
4,263m at Star and Comet underground, Nyamulilima, Nyankanaga underground, Selous and Geita Hill West underground.
Mineral Resource conversion drilling at Star and Comet Cut 2 and Cut 3 improved the understanding of the geological and
mineralisation controls of the deposits which led to the redesigning of mining stopes and underground infrastructure as well as
improving Mineral Resource confidence. Several intersections reported from Cut 2 exploration drilling confirmed the down plunge
extension of the main mineralised zone below the 1000mRL (LOM extent). Further drilling is proposed in 2019 to continue defining
the extension of mineralisation as well as confirming the geology and geometry of the deposit above and below the intrusive body
which appears to truncate mineralisation. Several exploration holes at Cut 3 were also planned to test the down plunge high grade
zone to 650mRL from the current 1000mRL (LOM extent). These holes confirmed the down-plunge continuity of gold mineralisation
which remains open at depth. The 2019 work plan motivates further drilling to continue defining the down-plunge extension of Star
and Comet Cut 3 as well as converting exploration targets into Inferred/Indicated Mineral Resource.
Drill results from Nyankanga Block 5 lower, 4 and 3 lower were used to update the Mineral Resource model in these areas and the
associated mining designs. The mineralisation at Block 3 lower continues towards Block 2, suggesting that the designed mining
stopes, (upper and lower) are linking up/down-dip and down-plunge. These results warrant further drilling in 2019. At Nyankanga
Block 4 the drilling results in the north east most section indicate open-ended potential downdip towards Block 3, suggesting that
the two Blocks are connected. Further drilling is required to follow up on these results. Drill results from Nyankanga Block 5 confirm
that mineralisation is controlled by the intersection of the Iyoda shear/faults and the Nyankanga Shear zone. Two exploration holes
were also drilled from surface to test the potential down-plunge continuity of gold mineralisation at Nyankanga Block 5 Lower.
The geological features that formed the basis of the targeting were not intersected, suggesting that the mineralisation has been
displaced. Detailed geological and structural studies are ongoing before planning for additional drilling.
E-W Geological cross-section through Star and Comet, elevation in mRL
Structure
LEGEND
Section definition boundary
Shear zone
BIF
Brecciated BIF (zone)
Dolerite
Felsite
Lamphrophyre
Lithology
Tonalite
0 12.5 25 50m
1,100
1,100
1,300
1,300
1,500
0
100
200
300
400
500
600
700
0
100
200
300
400
500
600
700
1,500
125
SECTION 3 / CONTINENTAL AFRICA
GEITA CONTINUED
At Geita Hill West, a drilling campaign was completed in November 2017. While this programme was successful, a second phase
of drilling was required which commenced in October 2018 with the intention of upgrading the Mineral Resource currently within the
underground mine designs/stopes at Block 1 and 2 to Indicated Mineral Resource ahead of underground mining development and
is expected to be completed in January 2019.
Expensed reconnaissance drilling programmes were conducted at satellite targets Selous and Mabe. Several of the drill holes
from Selous and Mabe reported encouraging intersections that warranted follow-up and consequently a conceptual mineralisation
model was created for Selous. The current conceptual model suggests economic viability of the project, and will require further
drilling in 2019.
A single phase of drilling was completed at Star and Comet NW Extension aimed at testing two potential mineralised zones away
from the intrusive unit. Drill hole SCDD0039 intersected two structures as expected, characterised by semi massive sulphides
(mainly pyrrhotite) in a breccia matrix. Significant gold assays were intercepted, associated with the first structure and remain
open-ended downdip.
One drill hole was drilled from underground at Block 5 targeting a 3D Seismic target (Target 1) at Nyankanga. The hole was targeting
a strong seismic reflector located immediately south of the Nyankanga pit. The drill hole encountered diorite and there was no
economic intersection reported from this drill hole.
Non-drilling programmes included a Down-Hole Electromagnetic (DHEM) survey at Star and Comet, Selous and Nyankanga to
delineate and identify relatively deeply seated or dislocated orebodies away from the main mineralisation. Several conductors were
identified during the survey and will be followed up in 2019. Detailed surface geological mapping and interpretation at Nyamulilima,
Kalondwa Hill, Samena-Fikiri-Jumanne, Prospect 30, Prospect 5 and Nyamonge Hill also occurred during the year.
An exploration workshop was also conducted on site in October 2018. The aim of the workshop was to review exploration targets
within the GGM mining and exploration concessions, identify new targets, re-rank existing and new targets and reevaluate the
endowment potential of the district.
PROJECTS
GGM’s exploration strategy is focused in three key areas. The first was to increase the Mineral Resource/Ore Reserve base of the
main producing deposits while transitioning to underground. The second key area was aggressive exploration of the satellite targets
within GGM’s tenement holdings to bring into production and the third was exploration activities to support major long lead projects.
Underground mining successfully started at Star and Comet Cut 2 in 2016. Development at Star and Comet Cut 3 was initiated
from the Cut 2 platform and was ramped up as planned in 2017. Detailed mine design, planning and permitting for Nyankanga
underground was completed in 2016 and underground development commenced at Blocks 4 and 5 in 2017. Underground
exploration drilling has successfully converted exploration targets and Inferred Mineral Resource to Indicated Mineral Resource
in these deposits. Following the successful implementation of underground operations at Star and Comet and Nyankanga
underground, exploration and development will be expanded to include Geita Hill and Ridge 8 deposits in 2019.
There are approximately 50 conceptual exploration targets within GGM’s leases. Resourcing this exploration programme, termed
the satellite target exploration programme, has lagged following the gold price decline in 2013 and reduction in spending. The
programme was re-planned and re-evaluated in 2017 and dedicated work plans have been put in place to support a more
aggressive exploration programme. Consistent with previous years, the targets that have the potential to provide near term value in
the LOM plan have been prioritised.
The Refractory Ore project which encompasses, Matandani, Kukuluma, Area 3W and Area 3CS was postponed due to high capital
costs related to plant modifications to treat the refractory ore and the transition to underground mining. Drilling was completed
in 2015 within the Matandani pit, which contains the largest Mineral Resource potential. Metallurgical scoping test work was
successfully concluded in 2016 and the PFS that was planned to commence in 2017 was put on hold.
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SECTION 3 / CONTINENTAL AFRICA
MINERAL RESOURCE
Details of average drill hole spacing and type in relation to Mineral Resource classification
Category
Spacing m (-x-)
Type of drilling
Comments
Diamond
RC
Blasthole
Channel
Other
Measured
–
–
√
√
√
–
√
√
√
–
–
–
–
Indicated
10 x 10, 20 x 20, 25 x 15,
25 x 25, 40 x 20, 40 x 40
–
–
–
–
Inferred
40 x 40, 50 x 50, 80 x 40
–
–
–
–
Grade/ore control
5 x 10, 10 x 5, 10 x 10,
10 x 15
–
–
–
Underground: diamond
fan drilling
Open pit: RC grid
127
SECTION 3 / CONTINENTAL AFRICA
GEITA CONTINUED
Inclusive Mineral Resource
as at 31 December 2018
Category
Tonnes